Why do guppies swim up and down?

Help - All Fish Swimming Up and Down Tank Glass? - All my fish are swimming up and down the side of the tank in one particular spot. read more

They swim up and down because they are: * Looking for food * (males) looking for anything remotely female-like to hit on * Avoid remaining stationary to make it more difficult for predators to get at them. read more

Guppies swim a litle hyper because their just learning as a baby is taking his/her first steps. read more

Whether the fish has a swim bladder disease or not doesn't mean the ammonia issue should not be taken care of or the tank properly cycled. The ammonia will kill as fast as any disease, if not faster and more than likely after or during cycling a tank with fish in it people end up treating for something else, as "ammonia" and "disease" are the two inseparable best friends. read more

When fish swim up and down against the glass, its called glass surfing and its usually an indication of stress. I had a lone pictus catfish that should have been in a shoal and he would glass surf in one corner of the tank all day long; in the pet store they seem to zip around in groups but never glass surf. read more