My neons seem to be experiencing difficulty, from straight after being fed, to about 30 minutes after, where they have difficulty swiming and seem to be forced to float to the top, tail-end first. They try to swim back down, but are overwhelmed by the mysterious "current". It seems to severely stress them. In some cases they've been floating on their sides at the top of the tank, and ive had to shake (!) the tank to force them back down to swimming level. This is occuring with ALL my neons, but seeing as my tank is only neons thats not much of a consideration.
Is this something that happens to all Neons? Is it because the food bloats them which forces them up to the surface? I wonder if its a sign of fin-rot or some other such disease?