What are these worms?

[dutchman]

I just noticed these tiny dark colored worms. They're very thin and only 1/4" long at best. Noticed a few on my waterfall and a few in the top tray of my biofilter. Just wondering if they're normal, where they come from, if the fish will eat them, etc.

 

[dutchman]

Maybe this pic may help, Check out thes little green things

 

[DrCase]

I dont know what they are , But if the koi can get them they will like them

 

[koikeepr]

are they actually moving around? It almost looks like poop! LOL!

 

[stroppy]

thats what i was thinking too koikeepr :0)

 

[dutchman]

Yes they definitely sqirm around. The only thing I have changed or added to the pond was a biofilter. Never saw these before that. The filter has been running for about 3 weeks, so I looked inside to see what was happening, that's when i noticed the critters.
I have surfed the net and haven't come to an exact match. But, I have read nothing about worms harming the pond or fish. In most cases it sounds like the fish would just eat the worms.

 

[stroppy]

just read up on them and they could be china mark moths otherwise known as sandwich worms ...google it they might be what you have

 

[DoDad]

I get larva in my system at times. Mine are mayflies and midge larvae. If I could get them into the pond that would be great. The worm larvae doesn't bother me but I hate those little black snails.

 

[koiguy1969]

I get larva in my system at times. Mine are mayflies and midge larvae. If I could get them into the pond that would be great. The worm larvae doesn't bother me but I hate those little black snails.

i hear ya... i moved some hiacynths from my filter yesterday and saw 100+ snails ended up totally dismantling my filter to clean out minimal 500 of those things. not to mention the egg clusters i pulled from pond stones.

 

[nigil]

I have them as well, they are some sort of insect larve,and represent a good balance in your water bacteria and system.

 

[TJeep_1999]

I get larva in my system at times. Mine are mayflies and midge larvae. If I could get them into the pond that would be great. The worm larvae doesn't bother me but I hate those little black snails.

Know this is an old post, but opted to leverage the search function over just posting a new thread. I had a similar discovery to the original poster. After some follow up research I'm 99% sure what I have are the midge larvae. Specifically the Chironomid midge (Maoridiamesa). Thank you for the helpful reply!