i am having a simiular problem. only i bought my fish yesterday (4 platies). before i went to bed they were kind of near the top looking like they are trying to get air. when i woke up, they were all still at the top and the water is cloudy. i also have a snail. could it be the snail? i have a whisper filter, and my tank has only been set up for 1 day!
I will reply in here also. So everyone here can help you so you wont lose your fish. Here is the first link. http/www.fishforums.net/index.php?showtopic=10099
I will give you another link on doing a fishless cycle on your tank if you decide to take your fish back to the store.
Here is the link on how to do a fishless cycle http/www.fishforums.net/index.php?showtopic=73365
I hope this helps you out some.