What type of colony is this and is it good or bad for fish?

[Ponder Koi]

Just discovered these today guys today emptying the skimmer basket, they are firmly anchored to the bottom and sides of basket in dens populations. Pond is less than 2 months old check water every week and organic levels are fine, i have seen minimal parasitic symptoms in fish such as flicking. Water temps get about 63 in day lot of shade big 15,000gal botttom pond. Just got a 25W UV sterilizer that fits into for my savio skimmer have been running it for 48 hours can that have anything to do with these guys appearance.
so is this protozoa or bacteria, larvae?

 

[Mmathis]

Well, they look like little wormy things......

How big are they? What size is that lattice, for a comparison?

 

[Ponder Koi]

Well, they look like little wormy things......

How big are they? What size is that lattice, for a comparison?

Those are about half inch squares so they are kinda large. Thought they were snail eggs at first but I don't think so, they are really weird im confused. I'm usually good at identifying these kind of things. There whole bodies and tails are anchored to plastic not free swimming what so ever. Can that rule out insect larvae?
I killed them all with salt dips to be safe, they turned white and ungripped enough to wipe off.

 

[Tula]

I don't know, but my guess is some type of insect larvae. Good idea on the salt dip. I'll be intereted to follow this thread and see what others think.

 

[Mucky_Waters]

Never seen those before, but if I was you I'd put that basket in the pond for a while and see if the fish will eat them off of there. I wouldn't worry too much about them, they are probably just some sort of harmless insect larva.

 

[fishin4cars]

I'm not sure what they are, but most likely a native insect larvae to your area. I normally leave these alone and let nature take it's course. For the most part if you can see life of filtration and it's not on the fish it's pretty safe. usually a case of natural food supply for the most part.

 

[callingcolleen1]

I get things growing on the filters and under the water way that look similar. They have been there for over 20 years now in my pond. I don't worry about them, and I am careful not to harm them as they have a purpose, and I think they are good for the filter as it makes the filter more "alive". My ponds are healthy, clear and the fish are all well and do not have any sickness. My two biggest oldest koi are over twenty years of age and they are all well, despite the funny things growing in the filter.

 

[Tula]

After reading other's replies, I'm thinking I should have said to let them be, rather than agreeing with the salt dip. Live and learn

 

[Dave 54]

I get things growing on the filters and under the water way that look similar. They have been there for over 20 years now in my pond. I don't worry about them, and I am careful not to harm them as they have a purpose, and I think they are good for the filter as it makes the filter more "alive". My ponds are healthy, clear and the fish are all well and do not have any sickness. My two biggest oldest koi are over twenty years of age and they are all well, despite the funny things growing in the filter.

Ponder koi we concur with Collieen on this it marks the fact that your filters are doing well and support life other than that of your koi.
We often see this when doing filter maintenance , I think they belong to a sort of lace wing small mayfly type of insect , you may even come across other insects in your filters we even see larval stage snails, red worms, small slugs and even woodlice living in the filter meadium .


Dave