I'm currently treating my dogface puffer in a HT for ich with hyposalinity.
I had him in a 35 gallon that sprung a leak due to the stand, so I quickly went out and bought a 30 gallon with a proper stand and moved him over. I cleaned the new tank out with vinegar and then rinsed out before putting the water/puffer in.
Ever since moving him over to the new tank he's barely been out from under the sponge filter, and when he does it looks like one of his fins are clamped. He swims around a little bit then looks like he is coughing/convulsing. Also when he is lying at the bottom I can tell he is having a hard time breathing and he is breathing pretty quickly.
He's usually up and around trying to get fed 3-4 times a day, but now he only comes up once every few days
Water params are ammonia - 0 nitrite - 0 nitrate - 0 temp 79 salinity 1.012.
I noticed when I bought the new tank that the silicone sealant was stained a black colour. I asked the guy selling it and he said that he had black gravel so I just figured it was stained by that.
Any ideas? Is it possilble that the old tank owner was medicating his fish with something that is affecting my fish now? Maybe he cleaned the tank with something? I asked if he ever used copper and he said no..