Unidentified critter

Question
QUESTION: I found a critter in my 20g planted tank. It is about a half inch strait long thin body. It has 4 or more legs a small rounded head (more like a fry than a shrimp head)and 3 or 4 tail fins that it propelled itself with. I caught it and put it in the fry tank thinking smaller tank with less hiding places would make it easier to get a better look. It burrowed into the gravel. Any ideas on what it is or how I could coax it out to get a better look?

ANSWER: I could tell you if you had a pic. It could be a lot of things.

Probably a large hydra, or more likely a wiggler but that depends on what other fish you have in the tank.

What other fish do you have in the tank?

---------- FOLLOW-UP ----------

QUESTION: Platies, danios, apple snail, pond snails.

Answer
Sounds like your fish just had babies!

It is likely the platies, but danios are also prolific spawners. You can try and catch and raise him if you would like, but if you leave it alone he may grow to adult size himself. The other fish will eat him if they have the chance, so he will stay hidden for awhile.

-Nick