[lochness]

hi - need to ask some more specifics - you said you cleaned the tank - vacuumed gravel etc - What is the etc? What other cleaning did you do? what kind of filter are you using and which fish is lethargic? When you say *the tank has been set up for a couple of months* is it 2mos, 4mos or is it 6mos? I'm not a big fan of Stresscoat nor Stresszyme (I use Prime) but how much of it do you use and which water conditioner are you using in addition to those 2 products? I would recommend buying Aquarium Pharmaceuticals Tap Water Conditioner in addition to those 2.

What is the ammonia reading? What kind of lighting do you use and how long is it on in a 24 hour period? What kind of substrate do you use and how thick is it?

I would stop doing water changes for now and do 25% in 2-3 days - by doing so many large water changes, you are slowing down the cycle needed to produce more beneficial bacteria and your readings will continue to be high in nitrites/nitrates. Also stop adding salt unless it is a brackish setup in which case add a bit less for now to speed up the cycle.

Is it a brackish setup or do you use just a pinch of aquarium salt? note: salt slows down the growth process of beneficial bacteria