Is my swordtail lonely or sick or what? Help!

[Kyohti]

fish are a lot different. they don't have emotional thoughts or needs like humans and other warm blooded animals do (at least not swordtails). he probably feels insecure alone, swordtails like groups.

No offense meant whatsoever... I just really found that cute in a tongue-in-cheek sorta way. ^.^;;

And I'd agree. Schooling fish tend to hide away when they are lacking tankmates of their own kind to fraternize with. When 3 of my 5 neons kicked the proverbial bucket, the other two became very secluded until I brought more neons home for them to swim with. Perhaps that's the problem?