My boyfriend has a ten gallon tank. A while back, there was some problem we never discovered that caused many of his fish to die over about a two week time span. He finally figured it was city water and since then has been using store-bought purified water and his fish have been great. Slowly...
5 gallon tank
Elite filter up to 10gallons
black neon, has been missing half his face since I got him (3 weeks to1 month ago). eye appears shrunken in the skull, possibly gone altogether. gill was already partially diminished, appears worse now. eye...