I just purchased a new tank for my betta(an upgrade to 2 gallons from .9 gallons) I washed the tank out with hot water as well as the plants and gravel and put water treatment in the tank and let it sit for a day before making the switch to this tank. Today I walked in on my betta seemingly stuck between the bottom plate and the corner of the tank, belly up. He is still alive, but I have no idea how long he'd been down there(could be up to 3 hours). I had to reach down and pull him up carefully and now he's swimming pretty slow and he keeps puking out food. I'm concerned that something is wrong with him because he was found belly up there, not a usual position for fish. I tested my water and the only thing slightly funny was the nitrite levels, and that wasn't very far off from where they should be(it was inbetween safe and caution and no where near danger). Could this be whats harming the fish? Will Sushi pull through this? How do I fix the issue?
I use aquasafe plus to treat the water each time I do changes, does that work with nitrite or? All of my other levels are fine and the tank is at a more consistant heat and the same heat as the previous tank. I have little testing stips and all other areas are fine and I used the same tap water as I had used with the previous tank with the same treatment method. So ammonia levels are fine, chlorine levels are great, ect.