Inches. -. A shoe size is a numerical indication of the fitting size of a shoe for a person. Several different shoe-size systems are still used today worldwide. In some regions, it is even customary to use different shoe-size systems for different types of shoes (e.g., men's, women's, children's, sport or safety shoes).
Types of Algae. Brown Algae (Diatoms)  This is the first type of algae that begins growing in a new aquarium. It usually grows on the gravel and glass. Unlike other types of algae, this type requires silicates in order to grow. By increasing light levels, this type of algae can be replaced by the more beneficial green algae. Brown algae can easily be scraped off the glass.
More Interesting Factsâ¦. There are more than 7,000 different species of algae. Most live in the oceans, but they also live in fresh water and even on land. Also, algae produce about 330 billion tons of oxygen each year. Phytoplankton are tiny microscopic plants-algae-that form the base of the marine food chain. Phytoplankton is most abundant in colder waters where there is an abundance of nutrients. There are three types of algae: red, green and brown.