Are they tiny white wriggling worms? I had these by the millions especially in the swirl/net filter(which is also a bio filter). After some reading I followed the advice of reducing my feeding and now they are gone. For me it was a case of overfeeding. If they aren't affecting the fish, and its not a crisis, you can try to reduce feeding and see what happens.
Feeding fish this morning and I found out I have a hundred + baby tilapia so I pulled up my stool and sat there and watched them, I then noticed long translucent "worms"? attached to the side of the tank, of course I had to take a picture so I could ID them. The photo attached is slightly adjusted and shot with a macro lens. It doesn't look quite like this with the naked eye it looks more clear or translucent. I would say it is 1/4 inch long. Any ideas? I would like to assume that my system is running fine since I have a lot of fry around. Thanks
Hum, maybe it's snail eggs?