Just got back home today. Ammonia levels didn't seem to be any higher than usual but they weren't any lower either. I did a 50% wc and used prime this time. I also put a nylon sock full of gravel from my other tank that seems to be cycled along with a used filter in my aquaclear. Its been up a month or two longerthan my goldfish tank. I didn't check the nitrite ornirate levels in that tank but the ammonia is 0 and the fish seem happy. I'm only assuming that it is cycled but I think that it is. I'm going to try to get a baseline reading on my tap water overnight.to answer your question I have large gravel in my gold tank and I'm running an aquaclear 110 (500) with foam on the bottom then a carbon insert followed by a nylon sock with gravel from another tank and.used filter and finally biomax. Sory about the typos I'm on my phone. : )