Thanks! Temp 27 tank size 6'Ã—3'Ã—2' 50% water change. Sump filtration. Its ok now when i put aquarium salt.What size tank? What temperature? How often do you do water changes? How big was your last water change and when was it? What kind of filtration do you have?
We need as much information as possible to help out.
My quick advice would be to do a water change of 30% every day for three days, add an air stone to your tank, clean your filter, add one tablespoon of aquarium salt per 10 gallons of water.