Instructions
Reduce how much you feed your fish on a daily basis. Any uneaten food sinks to the bottom and degrades into harmful chemicals like ammonia. Feed the fish only as much as they can eat in about a two-minute span and scoop out any remaining pieces with a fish net.
Reduce the number of fish in your aquarium. As a general rule, a 10-gallon tank can support about 10 inches worth of fish, meaning 10 1-inch fish or five 2-inch fish. More fish in a smaller space means more fish waste and stress, both of which can be harmful and even fatal.
Change the filter medium more often. The filter collects harmful particles, and activated carbon and ammonia remover neutralize fish waste. However, the particles may build up to the point where they push through the filter and the ammonia remover and activated carbon may be used up, requiring a change. You should completely change the filter medium about once every two weeks to be safe.
Perform partial water changes about once a week. These water changes should include swapping out about 20 percent to 30 percent of the water and replacing it with fresh, dechlorinated water. Many novices may want to change more than half the water at once, but this shocks your fish and kills them.
Remove any dead fish from the tank immediately. Leaving dead fish to decompose in the aquarium results in ammonia spikes that kill the rest of the tank's inhabitants.
Fish Keep Dying in a 10 Gallon Tank
A 10-gallon aquarium can provide some excellent decor to your house, especially if the tank is clean and taken care of properly and the fish are happy and healthy. However, nothing fouls up your enjoyment of a tank more than the death of a fish, and it can be plain frustrating when several continually die. There are numerous causes for fish death in an aquarium, most of which have simple solutions.