Moved from the 10-gallon cycled tank (parameters were FINALLY 0 ammonia, 0 nitrites, 0 nitrates) to a 29 gallon tank. Planned to run both filters but couldn't get the smaller filter to fit on the bigger tank, so I moved the filter media from the smaller filter into the bigger one. It's been 48 hours and things are strange. First of all, 2 fish are missing. I can't find them anywhere, though I haven't taken the step of moving the decorations. I decided to check the water and the numbers are so crazy that they must be dead somewhere in there. I have 4 guppies, 5 platies, and 2 red cherry shrimp. One platy and one guppy are missing. Checked the water today and I got: Ammonia .25, nitrites through the roof (somewhere between 2.5 and 5, hard to tell at night) and no nitrates. What should I do?? I've never seen nitrites like that, even while I was cycling. Please help!!