There's something wrong with my tank..?

Question

My angelfish had fin rot.

So, like on the melafix bottle, I've been treating my tank, every day.

I recently did a water change (after three days of treatment), and with it, I added the usual, something that prevents raising ammonia in the tank, aqueon water conditioner and aqueon water vitamins (it also conditions the water, but also promotes slime coats and puts some essential nutrients in the tank).

Everytime I medicate my tank with a water change, it's cloudy, and all the fish are fine, and after a day of cycling the water is clear. But as I was watching TV this morning, I could see my Pleco (who NEVER comes out, ever), Moose, swimming to the surface.

I've watched him do this three times already, and I don't think it's normal..

Both of my Angels, and Dwarf Gourami's are doing this, my Clown Loaches are fine.

Can somebody tell me what I need?

Answer 1

It sounds like lack of oxygen, are they gasping?

Put some more power heads in the tank to circulate the water and point 1 at the surface of the water to help with oxygen exchange.