worm like critters

Question
I have an approx. 3000 gal pond with a depth of 3-4 feet with 2 bog areas that have a verity of different plants. I have a large amount of fish because of a huge birthrate this year I think I went from around 30 to around 50. I have koi,goldfish,a large catfish,and three turtles. the last two time I cleaned my skimmer filter and the basket on my pump I found a bunch of little worm like critters sqriming around they are very small like 1mm. I'm just wondering if this is somethink I need to worry about.

Answer
Dear Duke,

I'm not sure to answer your question correct.
However I found following for you:
http://dnr.wi.gov/org/caer/ce/eek/critter/watercritter/keywormlike.htm
and
http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/pond/
Hope this helps.

Normally most worms are safe for fish however completely sure I'm not as I have no image of them.

kind regards,
Raf