What's Wrong With My Cory's???

[eurospage]

hello everyone! . . .I have recently changed my tank from gravel to sand. This seemed to be sucessful but one thing i have noticed in the past couple of day's is that my peperred cory's are lying on top of each other most of the time and are making strange moves up against each other. They also seem to be flicking on their side's in the sand. Could anybody tell me what their doing? or if this is a bad sign and anything i could do to solve this. Many thanks everyone.

Cheers Euros Page

[apistomaster]

If they are healthy then it sounds like you may be seeing eggs stuck to the interior surfaces within a few hours or days. The behaviors described resemble the courtship/spawning behaviors of Corys and C. paleatus is easily sent over the edge into breeding by a change of water conditions(freshet)
You will have that answered very soon. If it's something else you may have to treat them for disease but I don't think that's what you're observing.