Alright so I currently have a 10 gallon fish tank that my wonderful man got me for Valentines day to upgrade my overstocked 3 gallon tank to. When I started fish keeping this summer I knew NOTHING about keeping fish, though I did have the decency to attempt to cycle the tank for about a week before putting the fish in...it didn't work well I lost a lot of fish but by end of August/Early Oct had a stable healthy tank with 4 fish in it (2 guppies a platy and a albino cat fish). When I got the new tank I read online that I could seed the new tank w/ the old tank filter and all so I did that and switched my babies into the tank about a week later all levels looking good. A week or so later I put in some new friends for them and two weeks later they are all dead. The tank has been running in total for a month as of yesterday. I went away for the weekend and had given my room mate explicit instructions on feeding the fish...she apparently thought they were starving and fed them A LOT like 3 times a day for 3 days. needless to say I came home to 4ppm ammonia and 2 platys, 1 rubberlips pleco, 3 guppies dead and two albino catfish SOMEHOW hanging on (in total 6 of 8 fish dead). I was heart broken, she was distraught and I went into save the catfish mode lol. I did a massive (90%) water change, filled the tank half way, realized I still had a TON of waste coming up from the gravel, so filtered that again, filled the tank, tested and was down to .25ppm ammonia. I did another 25% wc immediately and am still testing at .25ppm. I plan on doing another 25-50% wc tomorrow morning. Wanted to give Meeko and Flit (the catfish)a break seeing as I feel they have had a very traumatic weekend. I don't have huge hopes that they will survive the night, though they are behaving completely normally, have a good appetite (I took their algae wafers away when I did the water change but I can see them eating stuff from the plants and rocks because there was THAT much junk in there!) and do not appear stressed in any way. Here is my question...did I do this correctly? Would any one have handled it differently? This is what my pet store guy recommended and all. Second question, what is my next step? Continue w/ the water changes and wait for it to drop? If the cat fish do die, do I replace them or wait? I am leaving to see my guy Saturday and won't be back till Tue so I am debating getting one fish to test stuff out (if the levels drop) while I am gone or just waiting till I'm back esp if the cat fish are still doing well. I guess I wonder about the fish because another forum said that leaving the tank already cycled w/o fish in it could harm the tank chemistry? Any advice would be wonderful!