Interesting Guppy Fin Question

Question

I recently got some guppies. 2 males and 8 females. They have their own tank. Pre cycled. 0 Ammonia, 0 Nitrite, 5 Nitrate. I keep the temp at about 76. Need a better heater, but the one I have in there is keeping it warm enough. It's been about 3 days since I got them and one of the males has developed a unique problem. His left pectoral fin is not moving. His right is fine, but is left is extended out at about a 45 degree angle from his body and just stays there. I don't see any signs of physical damage, and he appears to be moving around and eating just fine. I got the fish from two separate stores... a local store and Petco... I would have preferred to get them all from the local store, but they didn't have very many in. The male with the fin problem is from Petco.

Any ideas what could be wrong with him?

Answer 1

Probably just a deformity, or an injury it got before you purchased it.  

Answer 2

This doesn't sound like any disease I have heard of before. So I am just guessing that it may have been an injury quite possibly from the filter?! I don't really know but that would have to be my best guess. As long as your fish is swimming alright he should live a pretty normal happy life. I wouldn't worry about it to much.

Answer 3

Well. humans can be born with deformities, I am sure fish can too.

That's why you have to look clearly at each of the fish you buy..

Always observe them before you purchase....