What The Heck Are These!?

A few weeks ago I setup a 20 gallon Rubbermaid bin on my deck to breed trapdoor snails for my darters. Up until today it's just been a few snails and their babies, tons of algae, and anacharis in the bin. Well I go outside to look a few minutes ago and there's these disturbing looking tiny worm things with spines on their sides and one eye jerking around on the bottom and in the water column. I have no idea whatsoever what they are but I'd like to know what they are before I stick my arm in there for another water change.

Caught one in a syringe then out it in a jar to get a better look. It's yellowish tan with a black head/eye thing and it looks like it might possibly have a small stinger on the end of it. In the first picture it's
Under the I in the word in.

Ok, that's what I kind of figured. Well at least I've got some good insect food for my fish now . Yeah I need to get a few gambusia or something like that to eat them everytime mosquitos breed in there.