Oral lesions (mouth sores) make it painful to eat and talk. Two of the most common recurrent oral lesions are fever blisters (also known as cold sores) and canker sores. Though similar, fever blisters and canker sores have important differences.
You could do a school of White Cloud minnows, they require cooler water, so you wouldn't need a heater. I think if you check the profiles, the ideal temp should be no lower than 67 degrees. Not positive.or example: my goldfish tank is fine in the summer, but my house gets so cold in the winter that I need to have a heater to keep it above 70F. Fish need a constant temperature which is one of the reasons we use heaters.
Clean the skimmer basket and hair basket. The hair basket is the one located at the pump. 8. Turn filter handle to the BACKWASH setting, and then turn on the pump. 9. Continue to let the pump run until the water in the sight glass on the filter is clear. 10. Turn off the pump and set filter handle to RINSE, and then turn on the pump for about 60 seconds.