Upgrade Issues

Question
Hi! I'm not too sure if you can help me, for I am new to this site.
I have 3 fish, 2 fantail goldfish, and one shubunkin. The Fantails are like giant butterballs, and the Shubunkin is really.. long. I have had these fish for nearly 3 years. They started their lives in a 10 gallon tank, and I decided it was time to upgrade them to a 36 gallon tank. I set up the tank, let it cycle for 3 days, and then put the fish in. Everything was fine for the first few days, and then it went cloudy. The fish became tired, and were hanging out at the bottom. I took water samples, and it said my ammonia was really high, so I did water changes. Then I took a sample to PetSmart to get a 'professional' opinion. The girl told me to stop doing water changes, and to put a lid on the tank, so I did that. Then, within 2 days, the fish started acting weirder. I have hardly fed them. They're going to the surface, gasping. I went back today, and took another water sample. She said my nitrates and nitrites were really high, and that I should vacuum the gravel, so I did that. Then I did about a 30% water change. The fish are still really acting weird. Also, I noticed last night, there seems to be a whiteish.. fuzz, on some of the fake plants in the tank. I  think there might be an algae problem starting? Is this just part of the new tank cycling process? Are my fish going to survive. I'm really worried, because I'm rather attached to them since I've had them for so long. Is there anything else I can do to help them? Thank you for your help, it's much appreciated!

Answer
The best thing you can do at this point is set up the 10 gallon tank and put them back in it for now until you get the problem in the bigger tank sorted out. Keep the water changes going on the bigger tank take the plants out and wash them off with water. It sounds like you might have a fungus problem in there.  Ammonia is really common for new larger tanks I know when I moved my fish from 10-33 gallons there was a big mess with ammonia. But the best you can do is water changes and maybe adding something like 'cycle' which reduces ammonia levels.