Starting a fish tank for beginners - Complete Guide!

Starting a fish tank for beginners – Complete Guide!

So you’re thinking of setting up a fish tank, Great!

Keeping fish is a fantastic hobby and great fun for all the family. Starting a fish tank for beginners is lots of fun and if you follow some simple rules and best practices you’ll have good success and end up with a beautiful aquarium that will give you and your family hours of fun.

In our family, we love nothing better than going to the aquarium store and choosing fish for our family aquarium.

People start their first aquarium for many reasons but one of the most common is as a gift for a loved one or child. Beginner aquariums have become much easier to set up these days and like any hobby the more information and advice you have the easier you’ll find it.

There are many benefits to keeping a fish tank. They can help productivity in the workplace, they relieve stress, they can have a calming effect on children and often help children sleep better at night. Studies have also shown that fish tanks can help people who have Alzheimer’s disease.

In this article, we’ll offer some simple advice in plain English to help you get the most out of your first fishkeeping experience and hopefully, you’ll stay within the hobby for many years.

Facts, such as larger tanks are easier to keep due to the water quality being easier to maintain, are great tips that people often don’t know about when they buy their first fish tank. Often people buy a very small fish tank, or worse the dreaded Goldfish bowl and then wonder why their fish die very quickly. It’s due to the water quality being very difficult to control in such small volumes.

As responsible pet owners, we have a duty to provide the best possible environment and conditions for our fish. Learning what they need after you have purchased your tank, equipment and fish might be too late and could cause your fish to die prematurely.

We hope this guide on Starting a fish tank for beginners helps you make the right decisions and saves you time, money and the lives of some poor innocent fish.

Let’s get stuck in and help you enjoy your first aquarium.

What type of fish should you keep?

There are three main types of fish that you should consider keeping in a home aquarium.

  • Tropical Freshwater (Warm-Blooded Freshwater fish like neon tetras & Guppies)
  • Saltwater Fish (Warm-Blooded fish, coral, and invertebrates)
  • Coldwater Fish (Many species like Goldfish)

All three offer many attractions and hundreds of different species to choose from. Many will say that coldwater fish are the easiest to keep and set up closely followed by tropical freshwater fish. Saltwater fish are best kept once you have gained some experience in fish keeping. Gaining any experience in fish keeping from performing water changes to testing for water qualities will eventually help you to set up a stunning saltwater aquarium and help avoid any costly mistakes.

The process of setting up a Tropical Fish tank and a cold water tank are very similar. The only real difference is that tropical fish need a heater to warm the aquarium water. Saltwater is very different and we’ll go into that in more detail further in the article but basically, the water will be warmed by a heater and the water contains salt. The filtration and lighting are also different and the water conditions need to be checked regularly for changes which you’ll need to react to,to ensure the best water conditions possible which saltwater fish need in order to thrive.

All fish need great water conditions but tropical freshwater and coldwater fish can tolerate poor water condition better than saltwater fish making them easier for beginners to keep.

Best place for your aquarium

The simple task of positioning your aquarium in the correct place is often overlooked and can play a pivotal role in how successful your home aquarium will be.

If you’ve ever seen an aquarium that’s all green, full of algae and has cloudy water then the probability is, that is it’s placed near direct sunlight. One of the main reasons for excessive algae growth in a home aquarium is too much light. Placing an aquarium in an area where it can receive direct sunlight will only lead to issues.

Sunlight can also raise and dramatically lower the temperature within a fish tank. Since fish are cold-blooded species, they can’t regulate their body temperature like we humans do. Therefore it is vital that you maintain the correct water temperature both day and night. We use Thermostatic heaters to regulate the water temperature and Thermometers to monitor the temperature within the fish tank. There are many different types of Thermometers you can use from simple stick on the front glass types to digital probe thermometers. Read our complete guide to fish tank thermometers. 

Placing a fish tank near a room heater such as a radiator will also cause you problems with water temperatures. Fish are very nervous pets in the home and placing a fish tank near a door or entry point into a room will only make your fish nervous and stressed. One of the biggest killers of fish is stress, ensuring your fish are happy and relaxed in the home aquarium is part of being a responsible fish keeper.

Think about where you are going to plug in all your fish tank electrical equipment. Power sockets should be close by; try to avoid using too many extension leads and plug adaptors.

Lastly, place your aquarium where you will get the best out of it. Fishkeeping is fun, relaxing and I personally spend hours just sitting watching my fish tank after a hard days work. There’s nothing better!

Where to place a fish tank

(Where you place your aquarium is very important)

Children love to have fish tanks in their bedroom, but there are some things you should consider. Firstly, fish tank equipment has improved over the years and the equipment is much quieter, however, the quiet hum of the air pumps and filters can keep some children awake at night. Personally, my children found it relaxing and it helped them go to sleep quicker.

Be careful with small children how high you place the aquarium and ensure that if they reach up, there is no chance of them pulling it over. Safety should always be your first consideration where water and electrical items are used. All fish tank equipment is made with water in mind but other equipment in a child’s bedroom may not be, such as lamps, toys, and stereos etc.

Always seek professional advice from a qualified electrician before installing any electrical items. We have circuit breakers on all our fish tanks for added safety.

What you place the fish tank on is also very important. One U.S. gallon of water weighs about 8.35 pounds or about 3.79kg. That makes the average fish tank with gravel, equipment, and decorations weight over 100 Pounds. Therefore a strong and purpose-built stand is a must. Dressers and wardrobes are not designed to hold such a weight and could collapse under the weight.

Best size and type of aquarium for beginners

The best size aquarium to buy is the biggest one you can afford, maintain and care for. When you’re keeping fish it’s often said that it should be called water keeping, not fish keeping. Because that’s what you are doing, maintaining the best water you can for your fish.

Fish like most, if not all living things produce waste which if left untreated produces some horrible chemicals. Ammonia is a compound of nitrogen and hydrogen and is a fish-keepers worst nightmare if left uncontrolled and not dealt with in a suitable timeframe.

As fish waste and uneaten food are left untreated they will produce Nitrates and the ammonia will build up in the water and harm your fish. That’s where a filter comes into play which biologically and physically takes out the harmful nitrates from the water.

In a small fish tank, it’s very hard to control the water quality and takes skill to monitor and maintain good water qualities. In a larger tank, it’s much easier as you have time to react to any fluctuations in the water qualities. The nitrates build up much slower and you can remove them much easier with partial water changes.

Buying a small fish tank is also not fair on the fish! We have a duty of care when buying pets and we should always provide the best possible environment to keep them in. Many people say fish have a limited memory and therefore can live in a small space but is that really true. If fish forget things in 3 seconds then how come my fish know when someone comes into the room that they are about to get fed? Read our article Do Fish Have Brains?

Providing the largest tank you can afford and fit into your room is giving your fish the best chance of survival and a happy, clean and large enough area to swim free and happy.

We understand that budget often limits the size of tank you buy but please think carefully about the size of tank you purchase. Many people buy a 5 Gallon tank to start with and that is simply too small for most people to keep successfully due to the small amount of water and the issue we have just discussed.

For a few more dollars you can buy a 15 Gallon fish tank like the one below which will provide a better environment for your fish and an easier tank and system to maintain. These tanks even have filters and lights built in, keeping the process of setting up a fish tank as easy as possible. Simply add Gravel, water and a heater (For Tropical) and you’re ready to go. Condition the water (We’ll discuss this further in the article), add decoration and plants wait a short period of time (We’ll discuss this further in the article) and you’ll be adding fish before you know it.

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  • Dimensions: 16" W x 15" D x 15" H (41 x 39 x 39 cm)
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No matter what type of fish tank you purchase just give your fish the conditions a living creature deserves. They can’t talk and let you know they’re suffering so think about their needs and provide the best care possible.

Long gone are the days of keeping a goldfish in a bowl, even the smallest goldfish tanks are now commonly sold around 3 Gallons and have filters and lights built in. A fantastic improvement on a 1 Gallon Goldfish bowl with a stem of Egeria densa, an oxygenating plant that people think will do miracles inside that bowl. It simply won’t and it’s cruel to keep a fish in a small bowl.

The more space your fish have to swim, the happier and less stressed they will be. Stressed fish are more likely to contract a disease and fall sick as their immune systems are considerably weaker. When disease breaks out in a small tank it’s much harder to treat and control. In a larger tank, you can regulate their medication and cure them quicker.

Smaller tanks are harder to keep. Again, it sounds counterintuitive, but it’s true.

Smaller tanks will also have a limiting factor on the type of fish you can keep. We’ve all heard of the myth that fish will only grow to the size of their tank. In parts this is true, the effect of keeping fish in a smaller tank means their growth rate is stunted and this can affect their overall size. When fishes growth is stunted, they will become stressed and more susceptible to disease and illness. They will also live considerably shorter lives.

Imagine if you lived in a room with a very low ceiling and you had to bend over all day every day, your body form would also change, horrible to think about right? So let’s not do this to these beautiful fish.

Best filters for fish tanks

You may have seen it written, or heard it said that aquariums do not actually need filters. This is true under certain sets of conditions but certainly is not advised unless you want to put a lot, and I mean a lot, of time into aquarium maintenance. So, forget the no filter required theory, especially as a novice, and build your aquarium based on the filter necessary basis.

To put it simply the purpose of a filter in your aquarium is to clean the water of debris, toxic buildup such as ammonia and nitrates, and to aerate so your fish can breathe. The reason this is vitally important is that poor water conditions, to put it bluntly, will kill your fish! Remember, however, your filter will not do all the work for you, you will still have to perform aquarium maintenance on a regular basis.

When it comes to selecting a filter for your aquarium, there are five main factors you will need to take into consideration. These are:

  1. Filtration type
  2. Water volume
  3. Internal or external
  4. Price
  5. Filter Size

Filtration Type

There are three types of filtration and most filters generally use a combination of them. These are mechanical, chemical and biological with the most efficient filters available generally using all three. This does not mean, however, that you cannot successfully use a filter that only uses say two of the filtration types. It just means that they are more efficient and may extend the periods between aquarium maintenance.

Mechanical filtration simply traps debris within your aquarium ensuring the water is clearer. The debris trapped, however, will continue to contribute to your aquariums bio load making regular cleaning or replacement of the filter media a must.

Chemical filtration captures impurities in the water. Using carbons as your chemical filtration will have a fairly broad effect absorbing a good variety of dissolved chemicals. Resins, on the other hand, usually target specific impurities such as phosphate.

Biological filtration is the process in which beneficial bacteria break down toxins such as ammonia and nitrite. They are transformed into a nitrate compound which is far less toxic. Beneficial bacteria need a well-oxygenated place to grow which is where biological filtration comes in to play. Biofilters are normally filled with highly porous media through which the aquarium water is pumped.

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  • Power filter for aquariums up to 10 gallons
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Filter Type

Choosing a filter type can be confusing as there are several types available. There are box filters, outside filters, sand filters, sponge filters, canister filters and many more. However, three of these are by far and away the most commonly used and provide an option for most types of an aquarium. These are:

  1. Hang on back filter (HOB)
  2. Canister/external filters
  3. Internal power filters

Of the three types of fish tank filters we will cover here the hang on back, or HOB, as it is more commonly known, is the most popular. It works by sucking water up a supply tube from the aquarium and moving it through a series of chambers that perform the filtration. Once through the chambers the water then passes back into the aquarium.

The reason the HOB is the most popular of the filters available is that you can purchase a full range of sizes suitable for most home aquariums. It also hangs in the back of your aquarium tucked away neatly. When buying a HOB filter it is recommended that you purchase one that will filter the full water volume of your aquarium six times per hour. So, for example, if you have 50 gallons of water you would need a 300 gallon per hour filter.

Canisters are powerful filters that are best suited to medium or large aquariums, around 40 gallons or more, read our complete review and guide on these types of filters. Best filters for large aquariums. These types of filters provide three stages, filtration using mechanical, chemical and biological filtration. This makes them ideal for the heavier bioloads of large aquariums.

On the downside, canister fish tank filters or external fish tank filters as they are often called can be difficult and time-consuming to take apart and you will need a cabinet to hide them away in. They are, however, the best option for any aquarium with their immense filtration abilities. Again choosing one with the capability to filter your aquariums water volume six times per hour is recommended.

If you have a small fish tank then you can check out our guide for filters suitable for smaller aquariums in the link provided here.

Air Pumps

The majority of beginners guides to setting up an aquarium will not include the humble fish tank air pump. This is because they are not actually an essential piece of equipment needed to run a successful setup. Read on, however, and you will see why they are something that you should consider.

We have already talked about how fish need to breathe and that they need the water in their aquariums to be oxygenated to do this. We have also discovered that filters help with this due to the movement of the water they create. However, you really cannot have too much oxygenation, in fact, the more the merrier your fish will be, and this is where an air pump comes in. These, handy little pieces of equipment oxygenate.

The general train of thought is that by creating bubbles in your aquarium the air pump oxygenates the water. This, perhaps surprisingly, is not the case. Air pumps work by causing the surface area water to move, creating more contact with the air. And the more contact the air has with the water the more it will become oxygenated.

There are two ways in which you can use the air pump within your aquarium but both work on the same principle. The air pump is plugged into the electricity and a tube attached that goes into the water. From here the choice is yours, you can simply attach an air stone to the tubing and bury it into the substrate or attach a specially made ornament.

Always buy a fish tank air pump that runs quietly or it will drive you mad. Read ‘9 quietest fish tank air pumps’ to find the best one for you.

9 Quietest Fish Tank Air Pumps

Air stones come in various sizes from around a centimeter to many inches in length. They allow you to either have one concentrated area of bubbling, or a curtain of bubbles which could stretch right across your aquarium. The more spread out the bubbles are, the better the water movement will be that is created. Tip: adding a colored light strip to a curtain of bubbles can make them look incredibly impressive and dramatic.

However, it would be prudent to note that not all fish enjoy the bubbles created by air stones so for them a small concentrated area is better. For those fish that do enjoy them, and you’ll know if they do as they will swim through them like crazy, knock yourself out, and bubble away to your heart’s content.

Air pump ornaments work on the basis of the force of the bubbles or the bubbles themselves creating a certain look. The most popular air pump ornaments are generally ones such as clams, treasure chests, and other items that open. They work by having an opening and closing valve allowing water through and then stopping it alternatively to create the open and close feature.

Other ornamental looks you can create include waterfalls and volcanoes. The volcanoes, for example, shoot bubbles from their core making them look like they are erupting. The waterfalls are generally a little more elaborate, normally requiring two air pumps and sand to create the illusion of water falling down the rocks.

Aquarium Heaters

A heater is one of the most important pieces of equipment that you will need in order to ensure you run an aquarium that is a healthy environment for your fish. This, of course, only applies to tropical and saltwater fish, as cold-water fish do not require warmer temperatures.

The main reason you need a heater lies in the fact that fish cannot regulate their own body temperatures and need their water heated to stay healthy. Fish that are placed in water that is too cold will become sick, lethargic, and may even die.

The Right Heater For Your Fish Tank

When it comes to choosing the correct heater for your aquarium, there are five main types. These are:

  • Immersible
  • Submersible
  • Substrate
  • Filter
  • mini

Immersible heaters are used to heat the water in your aquarium by direct contact. The temperature is controlled with a heating pad that must be placed above the waterline. This can make it difficult to install this type of heater properly in your aquarium. Immersible heaters are not a popular choice with fish keepers.

Submersible heaters have their temperature control built in making them far easier than immersible heaters to position in the aquarium. They are far and away the most popular kind of heater in the aquarium world. You need to be careful when choosing a submersible heater, however, as not all heaters advertised as submersible are fully submersible. Some need to have the top of the unit placed out of the water. This does not affect the way this heater will perform, just limits the positions and angles you can place it at in your aquarium.

What size of aquarium heater to use

(Aquarium heaters with thermostats are essential for tropical and saltwater fish tanks)

Substrate heaters are a cable heater that is laid in the bottom of the aquarium. They should not be laid on the glass as this will mean heat will escape, rather they should be laid on top of a layer of the substrate with another layer of substrate on top. Substrate heaters are not particularly popular with aquarists despite the fact that they are reputed to be extremely beneficial for live plant growth.

Filter heaters are basically filters with heaters built in. This means that the water is heated as it goes through the filter and is passed back into the aquarium. Surprisingly, they are not an overly popular choice despite the fact that they spread the heat around the aquarium better than the other heater types.

Mini heaters are a relatively new type of heater created for those who keep fish species such as the betta in mini aquariums and bowls. They are great at doing the job they are meant to in spaces too small for standard heaters. It does need to be noted, however, mini aquariums and bowls are not particularly healthy environments for any fish.

The Right Heater Size For Your Aquarium

Once you have chosen the correct type of heater for your aquarium, you will need to work out what size you require. Heaters come in sizes from around 25 watts to approximately 600 watts with the size you need depending on the water volume of your aquarium.

A general rule-of-thumb guide to working out the wattage that your aquarium needs is 2.5 to 5 watts per gallon. So, for example, an aquarium of ten gallons would require a heater of 25 to 50 watts, whilst an aquarium of 100 gallons would require 250 to 500 watts.

It is certainly worth noting here that whatever wattage your aquarium requires; you do not have to buy one heater of that wattage. You could also choose to buy multiple heaters that add up to the required wattage. Using the 100-gallon aquarium as an example and assuming you choose 500 watts, you could buy two 250 watt heaters or even two 200 watts and one 100 watts. There are no rules regarding this, but there are benefits.

Read our complete guide to buying an aquarium heater, best aquarium heaters.

Placement Of Your Heater

The main benefit of buying more than one heater for your aquarium falls under where it is best to place them due to heat distribution. After all, you want and need an aquarium that is heated evenly and doesn’t just have warm spots. Just one heater, even of the right wattage, has trouble doing this in a large aquarium.

By placing two 250 watt heaters in a 100-gallon aquarium at opposing ends you can ensure that more of the water is heated and evenly. By placing a third in the middle you increase the chances of even heat distribution even more. The same is also true of smaller aquariums although of less importance and less practical due to space.

For smaller aquariums, it is recommended that you place the heater close to water flow inlet or outlets. This will ensure even heat distribution through the movement of the water. Many fish keepers also recommend placing the heater close to the bottom of the aquarium horizontally as heat rises. You can only do this, however, with fully submersible heaters.

Aquarium Lights

On a base level, lighting your aquarium up allows you to view your fish even in bad natural lighting conditions. However, this is not the only reason that we use lighting in aquariums as it also, and more importantly, provides vital energy to photosynthetic plants and animals. Put simply, lighting aids in plant growth and keeps your fish and their colors in peak condition.

Which Type Of Lighting To Choose

The type of lighting you purchase should be based on which is best for the type of aquarium you will be running. For example, are you going to be growing live plants? What species of fish will you keep? Many plants need strong lighting to grow to their capacity and fish species vary in lighting requirements too. The main three types of lighting for aquariums are:

  • Normal output fluorescent lighting
  • Compact fluorescents (metal halides)
  • LED (light-emitting diode)

Normal output fluorescent lighting is arguably the easiest way to light your aquarium. It is affordable, relatively energy efficient, and can be used with a wide selection of bulbs. This means you can customize the type and color of lighting you provide.

fish tank lighting.

(Perfect lighting will not only help plants and corals grow but also make your aquarium look amazing)

Compact Fluorescents provide a higher output to normal output fluorescent lighting. They are available in dual and quad tubes with each bulb doing the job of two normal output fluorescent tubes. This type of lighting is also available in many types and coloring such as:

  • 50/50 or actinic white bulbs
  • Colour enhancing bulbs
  • Full spectrum/daylight bulbs
  • Actinic bulbs
  • Plant bulbs
  • High-intensity bulbs

50/50 bulbs are a blend of blue and white lighting that recreate but are not exclusive to marine conditions. They encourage coral growth and are pleasing to the eye.

Colour enhancing bulbs emit the warmer end of the color spectrum and display fish color to the optimum. They are ideal for fish only aquariums with no live plants.

Full spectrum/daylight bulbs emit all wavelengths of light and closely mimic natural sunlight. These are suited to all aquariums and ideal if you like the natural look.

Actinic bulbs display predominantly blue light and copy deep water conditions. They are most suited to reef tanks as they provide the necessary light energy for coral growth.

Plant bulbs provide light that will stimulate plant growth. They are in the red and blue regions of the color spectrum.

High-intensity bulbs shed crisp white light and are usually used with actinic bulbs in marine aquariums. This creates a brilliant blue and white light that appears cool.

The final choice of lighting for your aquarium is LED which has a low energy consumption, low heat output, long life, adjustable light intensity, many color options, and great coverage of your aquarium.

   Cheapest LED Fish Tank Lights On Amazon

LED is far and away the most popular light choice with aquarists today for the following reasons:

  • LED lighting uses 80% less electricity than fluorescent.
  • LED lighting creates less heat output so doesn’t have any effect on your aquariums temperature.
  • LED lighting will run for up to 50,000 hours, 6 years, compared to the 6 to 18 months than standard fluorescent bulbs last.
  • LED can be dimmed and programmed to mimic sunrise and sunset. This is particularly good for nocturnal fish as it will also create moonlight.
  • LED lighting comes in a wide variety of colors including magenta, green, blue, and red. You can also buy units that will color change.
  • LED lighting is usually arranged in strips so give an excellent aquarium coverage.

LED aquarium lighting does, however, come with some downsides including that the upfront cost is usually higher than that of fluorescent lighting. Many plants are also not suited to LED light as they need high intensity which LED does not provide. This will not, however, be a problem if you use low/medium light requirement plants.

Gravel or Substrate? Which is best for beginners

The chances are that you will have already decided to have some kind of substrate in your aquarium before even reading this. So, you may ask why are we covering it? Well, the answer to this is that not all substrate is created equal and that you will need to consider the type your aquarium may need.

Before we move on to the various types of substrate available, it would be prudent to explain why fish keepers use it. It is not, contrary to popular belief, just to create a pleasing aesthetic. The substrate also creates a healthy habitat for your fish.

Without going into too much technical detail a healthy aquarium needs a healthy nitrogen cycle. This is where friendly bacteria convert harmful ammonia into nitrate. Substrate helps in this cycle as it is a place where a significant number of friendly bacteria will live and grow.

When choosing the right substrate for your aquarium it is useful to consider the species of fish you are going to keep, and whether you are going to grow live plants. If you don’t, and you later discover you have chosen the wrong substrate it is not that easy to change! The following are some types of substrate and reasons you may choose them.

Gravel is the first and most common option chosen. This is probably because it comes in so many different guises. You can get natural and neutral colored gravel, neon gravel, in fact, any color you like gravel, and it comes in various shapes and sizes. Gravel is suitable for most aquariums but you may want to consider that it can be harsh on the undersides of bottom-dwelling species.

Sand is another fairly common substrate which again comes in various color options. As it is much finer than gravel, it is the preference of those who keep bottom dwellers. It is also really good for fish that like to sand sift searching for food. On the downside, aquarium sand can be expensive and needs thorough rinsing before use to avoid a cloudy aquarium.

Far less common but very attractive is crushed coral which has the advantage of raising the pH of the water for those fish species like cichlids which prefer alkaline water. Crushed coral is not generally found in pet stores but can be sourced easily online.

The final type of substrate we would recommend is laterite or vermiculite which is placed beneath other types such as gravel or sand. These are especially good for plant growth as they contain and release important nutrients to help plants grow. Of course, you only need this if you plan on having a live plant aquarium.

The amount of substrate you buy will depend on the size of your aquarium. Roughly you want it to be 1.5 to 2 inch deep except for sand which should be 1 to 1.5 inch. When using plant substrate and an additional top of another we would recommend half and half.

Aquarium Decoration and Planting

Plants and decor in an aquarium are all a matter of personal preference mixed with a little bit of care for the species of fish you are keeping. For example, some fish need plenty of hiding spots to stay happy and healthy, some need heavy decor they can’t destroy. And others, well, they just don’t really like decor at all!

Presuming you are keeping fish that will not be bothered by and will benefit from decor the first consideration should be plants. These are probably the most important form of decor as they can be used by your fish for hiding, resting, and even breeding. Your initial choice of these is pretty basic, live or fake?

Many fish keepers prefer fake plants as they come in a variety of colors that live plants cannot be found in. Most live plants are a shade of green with the occasional ones having a reddish tint. However, live plants benefit your aquarium more as they improve the quality of your water in more ways than one. Firstly they require nitrogen which they can take from fish waste, and secondly, they use CO2 for their respiration. This CO2, in turn, gives off oxygen for your fish to breathe.

Once you have chosen plants, you may want to consider other forms of decor such as tunnels, ornaments, driftwood, rock, etcetera. Every pet stores shelves are crammed with these making it very easy to find something for everyone. Be aware though that you may want to reign in your decor ideas as every ornament you put into your aquarium takes away space from your fish and decreases the water volume.

You may also want to consider checking that:

  • Ornaments do not have rough edges that could tear delicate fins
  • Holes in ornaments are big enough that your fish can’t get stuck
  • Bigger fish will not be able to knock the decor over
  • Plastic ornaments near heaters

Some fish tanks are built with just plants in mind, Aquascaping is an art form that recreates beautiful underwater scene that will simply amaze you. They do usually add some fish as well but they are mainly shoaling fish to compliment the plants. See the example below!


(Aquascaping is recreating underwater scenes from rocks and plants)

Filling the aquarium

The time has finally come when you can think about adding water to your aquarium. This is the fun part and the time when it all starts to come together.

The best way to fill a freshwater aquarium without disturbing the decoration, gravel, and heater, is to place a ceramic plate on the gravel or Sand and gently pour the water onto the plate. This will stop the gravel and decoration being moved around.

Fill the tank to within 1″ of the top line of the aquarium. The next stage is to use a water de-chlorinator such as AQUEON after filling and add a tank starter. We’ll go into why you should use a water de-chlorinator in more detail in the next section.

Tank starter is used to speed up the natural biological cycle within the tank, adding live bacteria into your tank will establish good water qualities within the water, filter, and gravel quicker. This will allow you to add fish quicker rather than waiting for natural bacteria to establish on its own.

The best way to fill a saltwater aquarium is to purchase RO-DI water from your local store. RO/DI water is short for Reverse Osmosis De-Ionized water. It is highly filtered water that is normally around 99% pure water. You can buy an RO-DI unit and convert your own tap water into RO-DI water or buy it from your local pet store or aquarium store.

RO-DI is a filtration method which forces water through a series of filters, the last one being a semi-permeable membrane that removes 90-99% of tap water impurities. The result is water that is free of minerals and other contaminants, such as chlorine, chloramines, pesticides, nitrates, and metals. All of which are harmful to marine life.

Saltwater aquariums will also need the correct level of marine salt adding and mixing into the water. Again you can buy this from your local store already done or you can buy it yourself and add it to the RO-DI water. You will also need to add a suitable tank starter like in the freshwater aquarium this will give a boost to the bacteria levels within the aquarium which will mean less time waiting to add fish.

Do you have to use RO-DI water? No, but if you want to get your tank off to a great start then why wouldn’t you use the purest water you can get which will also speed up the water cycle time. Keeping saltwater fish is all about water quality and testing to see what’s in the water that may harm your fish.

No matter what water you use you will need to run all the water tests you need to ensure the water is suitable to add fish. This can vary in time from 4-6 weeks depending on the size of the tank, water used and how much tank starter you added. Make sure you use a top quality water test kit. Here’s our favorite for both Freshwater & Saltwater available from Amazon. 

Fliing an aquarium with water

(A simple way to add water to your new aquarium without disturbing substrate and plants)

Water Conditioner

The temptation to buy, set up, and add fish to an aquarium all in one day is immense. However, you really should not do it. You need to let your aquarium cycle, at least for a few days! By cycling, we mean getting the nitrogen cycle going which is vital to your aquarium.

There are several ways to perform a fishless cycle in your aquarium, some of which are complicated and take forever and a day. We will not even go into these here as there is a simpler way that can be completed in just a few days. This method is suitable for fish that are hardier which most novices will choose to keep.

First, you will need to set up your aquarium ensuring heaters and filters are set running. Then simply add your choice of water conditioner in the correct amount and leave for approximately 7-10 days. Finally, and this is the really good part, go and buy some fish. Don’t buy too many at first, add a few at a time to allow your tanks natural biological structure to cope with the fish waste that will quickly build up. Too many fish and it simply won’t cope and the levels of ammonia will harm your fish.

For those of you thinking that was simple, well it really is! The water conditioner will have kick-started your nitrogen cycle and the fish when you add them will continue it.

In saltwater tanks, the cycle is much longer and you will need to test the water every week and monitor the results. Only when you think the levels are safe should you add marine fish. This process can take several weeks. Again you can kick-start the process by using a top quality tank starter like aquatic experts water conditioner.

Water Cycle

What is the fish tank water cycle and why is it so important?

Well, let’s try and keep this simple. Fish poo produces ammonia which is harmful to your fish. Imagine swimming in your own poo all day… Not very nice hey?

The nitrogen cycle (also known as the water cycle) is the process that breaks toxic nitrogen waste (poo) in your fish tank into less harmful components. For this cycle to work, beneficial bacteria that feed on these waste products need to grow in the aquarium’s filter system.

These filters use biological media to help the good bacteria grow and turn the harmful ammonia (toxic) to convert to nitrite (toxic), then nitrite to nitrates (non-toxic) unless it’s in high amounts.

Adding fish to a fish tank without a healthy nitrogen cycle in place is dangerous to the fish and can and often does lead to their death.

Even after the cycle is complete and your filtration unit is working well you will still need to perform partial water changes to remove and control the amount of Nitrates left. If nitrates are left to build up they will eventually cause issues within the aquarium. They can cause excessive algae growth, discoloration of the water and harm to your fish.


The length of time can vary for the full water cycle to take place to the point where it’s safe to add fish. Anywhere form 2 weeks to 2 months depending on the size of the aquarium, type of fish, and equipment you use. You can add a natural biological liquid that can help the process go faster as you are introducing good bacteria quicker.

For saltwater fish tanks we use API QUICK START and for Freshwater/Coldwater we use ATM BACTERIA both these products will help you speed up the water cycle so you can start adding fish sooner.

During the water cycle process, the ammonia levels will rise and fall as nitrite starts to build up and take hold in your water. Nitrate will not appear until your tank has significant levels of nitrite. Once it hits the correct levels, nitrate will form and your nitrite levels will fall. When you can no longer detect nitrites, you can assume that it’s safe to add your fish. The best way to test if the cycle is complete is to buy a test kit and perform weekly water checks until you’re happy the water is safe to introduce fish.

Think of the water cycle as a three-stage process

  1.  Ammonia, Introduced into your aquarium via fish waste or uneaten food.
  2.  Nitrite is a byproduct of a bacteria called Nitrosomonas, this organism will oxidize the ammonia – turning it into nitrite. The bacteria eat ammonia and produce nitrite, which is also highly toxic to your fish.
  3. Nitrates, The final part of the Water Cycle. Once your nitrite levels have reached a certain point a bacteria called Nitrobacter will develop. This will convert the nitrites into nitrates.

At this point, you are safe to start adding fish in small numbers. At this stage, your aquarium is still fragile and the water conditions could easily spike if you rush things. Don’t add to many fish at once, allow the good bacteria to build as fish waste increases.

Nitrates aren’t toxic to fish in low numbers, however, if they rise too high they’ll become toxic to your fish. You’ll need to monitor the levels in your aquarium using a test kit.

In freshwater aquariums, you can add plants and gravel to help fight the build-up of Nitrates. They help to produce good bacteria and break the nitrates down naturally. The best method to reduce nitrates it to perform a water change, which is a simple and effective way to remove nitrates. The recommended amount is 15-20% of your tanks water should be changed each week. For an in-depth look into performing, partial water changes read our guide on HOW TO CHANGE WATER IN A FISH TANK. 

It can be very tempting to add fish to a tank before it’s ready. After all, you see your beautiful, clean and shiny tank just sitting there and it looks amazing. But don’t be fooled, you can’t see ammonia, nitrites, and nitrates. Just because you can’t see or smell them doesn’t mean they are not there. Don’t rush things, fish keeping takes time and patience to get it right. Success comes to those who wait!

When and how to add fish

When your aquarium water has gone through the full cycle and the water is safe to start adding fish you need to know the correct way to acclimatize your new fish to the water in your tank.

What is acclimatization? Acclimatization is the process of introducing fish to a new environment without causing stress or any sudden changes.

What this means is that the water temperature in the bag you have brought home with you will have cooled down significantly. Therefore you need to acclimatize the water in the bag to the water in your tank so your fish don’t get a shock to their system when you add them to their new home.

The best way to do this is to open the bag and roll the plastic bag down to form a float around the bag. Then float the bag in the tank for 20 minutes. Slowly add a small amount of water from your tank into the bag every 5 minutes or so until the bag starts to sink which should take around 30 Minutes. This will allow the water temperature to stabilize and the water properties ie: pH, salinity, and hardness to equalize.

Then take the fish out of the bag with a net and gently add it to the aquarium. Don’t tip the water from the bag into your aquarium as this could introduce disease into your aquarium. Dispose of the water down the drain.

Don’t be tempted to simply open the bag as soon as you get home and tip both the water and fish into your aquarium. You run the risk of stressing the new fish which could kill it as well as introducing disease into your tank. Neither is a good thing!

How to add fish to your aquarium

Adding fish to your aquarium in the correct manner is very important for a couple of reasons. You may hear the term ‘Fish Acclimation’ this is the process of introducing new fish to your aquarium in the most stress-free manner possible.

There are many different ways to do this, but we will explain the most simple way to acclimatize your fish to their new home in a few easy steps. The Youtube video here also explains it in a good manner.

Feeding Guide

There are many different types of fish foods but most people often start by feeding their fish dried flake food. Whilst this type of fish food has come a long way over the years it very rarely offers a full and well-balanced diet for your fish.

The main types of fish food are:

  • Flake Dried flakes that float for a short length of time before falling.
  • Grain, pellets & Granules. These come in a variety of sizes some float, some are sinking
  • Wafer  Slightly bigger sinking wafers to help mid to bottom feeders get a share of the food.
  • Tablet, Fish food that can be dropped to the bottom of the tank or stuck to the inside glass.
  • Live foods These foods can be purchased in small single feed portions from your local store
  • Frozen Foods Keep in the freeze and break off a small portion when required.
  • Dried Foods Foods like Brine shrimp, bloodworms and Mysis shrimp freeze dried for long life

Many manufacturers now provide food for specific species of fish like Catfish, Cichlids and many more species. These offer a better balance for specific types of fish which may need a specialized diet.

Most fish will need to be fed 2-3 times a day, feed small portions and no more than they can eat within a very short period of time approx 2-3 minutes. If the food starts to drop and settle on the tank floor then you have overfed your fish.

Overfeeding of your fish is one of the worst things you can do to your tank. Overfeeding will cause poor water condition, will block and reduce the performance of your fish tank filter and can contribute to spreading disease throughout your aquarium. Old food will sit and rot away, don’t think that fish will eat anything and clear the rotten food, they won’t, even catfish won’t eat rotten food.

Give your fish a varied and quality diet. As a responsible fish-keeper, it’s your responsibility to provide your fish with the best possible diet. They are in your care and if you can’t provide a well-balanced diet then you shouldn’t be keeping fish or any pets for that matter.

If you overfeed your fish the best method to correct the issue is to perform a partial water change. How to perform a partial water change is explained in the next section.

What happens when you go on vacation? Well, you can buy an automatic fish feeder. They are very simple to use and set up and cheap to purchase. They sit on top of your tank with or without a lid and slowly turn to release food at specific times. They are limited to the types of foods you can use but whilst on vacation, they are the best method of feeding your fish safely whilst you’re away.

   Best Automatic Fish Feeders On Amazon

Store your fish food in a cool place in an airtight container to maintain its vitamin value and ensure your fish get the maximum nutritional value. It’s also best to buy small amounts, a month’s supply at a time, to prevent the food from losing its nutritional value. Don’t be tempted to buy in bulk as you will only end up wasting most of it, or worse, feeding it to your fish and unknowingly not providing them with the vitamins and nutrients they really need. This will eventually be to the detriment of their health.

We have many fish food reviews on our main website but here are a couple you may find helpful- Best cichlid fish food and Best catfish foods 2018-2019

Water changes & Maintenance

Water changes and maintenance are just a fact of life if you own an aquarium. You should never think that you can avoid them or not do them regularly. They are an important means of keeping the water quality good in any aquarium, freshwater or saltwater. Even hardy goldfish should have good quality water.

fish tank water changes

(Regular water changes are vital to the health and care of your fish)

As responsible pet owners and fish keepers we have a duty of care to our fish and by doing regular partial water changes we are giving our fish the best possible water conditions. This along with good quality foods and the correct size aquarium will ensure you’re doing all you can to give your fish the best possible life.

How would you like to swim around in your own poo all day? Not a nice thought, hey!

Read our complete guide on how to perform a partial water change in a freshwater fish tank.

Final Thoughts

We hope you have found this basic guide to setting up an aquarium helpful. There are many different ways to do tasks and setup aquariums so you may not agree with everything in this article if you’re an experienced aquarist.

However, this guide was written with the beginner in mind. Just some basic facts and tips for helping you set up your first fish tank.

Many people buy a fish tank for Christmas or for a Birthday gift without much thought about what it takes to set up a new fish tank.

Our website has many articles on various tasks and equipment to help you set up and run your fish tank successfully and to avoid the many mistakes we all make throughout our journey of keeping fish. Every day in fish keeping is a school day.

Read our funny article called 30 Fishkeeping Mistakes Beginners Make. This will help you to avoid some of the pitfalls we all make.

Enjoy your new fish tanks and please let us know how you get on.

Remember you can always join our fishkeeping Facebook group to talk to our fish keepers, have fun and make new friends. Fishkeepers are always ready to offer good advice should you still need it.

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