black skinny worms

[myredheads]

Hi All.. I hope someone can help me. I have a 30 gallon freshwater tank that has been up for 4 years. Every once in a while i find these skinny black worms on the inside of the tank and also on the inside of the lid. When these worms "mature" they end up as black flies. When they are killed, they leave a black power on whatever they have touched. Please help me.

Thanks
Mary

[MrGoodbytes]

You might have some kind of blackworm. As long as they're not fish bloodsuckers, like dragonfly larvae, your fish will probably just eat them. Live food :).
That's what it sounds like to me, but I'm sure someone more reliable can confirm or deny this.
BTW, welcome to AC!

Graeme