Post a pic in the SW
section and include a list of all equipment and everything that is in your tank. Describe the fish sizes in inches and include the name (species or common name) as you know them (if you do).
Do you have test kits for pH, ammonia, and nitrite? If you do, post those water parameters too.
When I had a FW
tank I learned that the best thing I could do to maintain the fish was a weekly 10% - 20% water change. In a tank of your size I woudl try to change a gallon out every 3 - 4 days to maintain high water quality for the fish.