Household pipes add metal to standing water. Keep tank out of sunlight. Common signs of infection are white spots, cottony patches, dead-appearing areas on body, ragged fins, clamped fins or sluggish fish. Most filters remove medications, making repeated applications necessary. Avoid bug or deodorizer sprays and paint fumes around tank.
Most sprays can hurt fish.
Be sure all four corners of the aquarium touch table before filling tank. Avoid using seashells, coral or sharp rocks. Avoid soft rocks such as limestone that dissolve in water. Never place tank close to air conditioner or heat register. Use at least one catfish and one algae eater for each five gallons.