First off, I want to say that we made a mistake in our big tank. Petsmart steered us wrong(of course we should have done a little more research too), in setting up our tank. Its taken over 2 months for it to almost complete cycling. Last night we had noticed several fish acting weird(mollies sitting at bottom, several hiding) and tested water. Ammonia was about .25, nitrites were about .25. We did a 50% water change, and tested again, and it was normal. Waited about an hour and a half and tested again, and nitrites were still about .25, and did a 25% change. Fish seemed fine after the changes. This morning we tested water and nitrites were still at .25. We had done a fishless cycle on a secondary tank and it had completed its cycle (0 ammonia, 0 nitrites, 20 nitrates), so we moved all our fish into it. Its smaller(from a 55 gal to a 37), and tonight tested water in it. Ammonia is barely there, but nitrites were .5. The fish had been in the tank about 12 hours. What could have caused this, and what can we do to fix this? We have been dosing tanks with Amquel+ (ammonia elevated right out if tap), and its not done anything to help. Any help would be appreciated! Thanks!!