Question
The worms I was calling bloodworms do not have any legs which I can see. If they are tubifex or blackworms, or even bloodworms, how do I get rid of them. They are mainly in the left over food but some are in the filter also. They appear to be in small dark brown tubes to begin with. They work their way out of the small dark tube like things. I thank you so much for a very good answer to my first question Robyn. Pat
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-----Question-----
I am having trouble with the little redworms in my fish tank. It is a 150 gallon tank in which I winter plecostomus. From all I read I assume they are called blood-worms. I would like to know how they get started to begin with. Thank you very much Robyn, Pat
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They sound like bloodworms but could also be Tubifex or blackworms.  If they are a bright red and have little tiny legs, they are bloodworms which are insect larvae (of midges which are like gnats) and in fact, not worms at all.  When the bloodworms mature, they will pupate and turn into little flying midges.  If they can then lay eggs in your tank, the cycle will continue.  I have some sort of midges in my 40 gallon pleco tank myself (not bloodworms though).  I don't worry much about them.  I try to avoid poisons.  Are the red worms in the tank itself or hiding in the gravel or filter?  If out in the open, adding some small tropical fish to eat the worms should work.  If in the filter, give it a good cleaning.  Midges can fly into your house and lay eggs or the eggs or larve can be brought in from your pond if you bring in anything from there (fish, plants, etc.).  If you have actual worms, they can come in the same way but certainly won't fly in.  Either way, they are pretty harmless.  Good luck!

Robyn
fishpondinfo.com

Answer
The tiny legs at the front of bloodworms are hard to see.  You may not see them without a microscope.  Bloodworms are bright, bright red.

The "worms" are eating the leftover food?  First, then I would use a gravel vacuum to remove that food and the worms in it.  Try feeding less food in the tank.  Aha, small black tube homes!  That was helpful.  Only the larvae of certain true midges (like bloodworms) and the larvae of caddisflies have those little homes.  True worms do not.  So, basically you have baby insects.  They will eventually turn into flying adults.  If you can catch them before they breed, there won't be more babies. To catch them, wipe them off the lid where they will congregate and maybe put up some sticky fly traps around the tank.  Fish love to eat both bloodworms and caddisflies if they can reach them. Certain animals and fish are more apt to eat them.  Plecos are too big to eat them.  What other fish do you have?  I have sections on all these animals.  Here's my bug index:
http://www.fishpondinfo.com/bugs.htm

I think adding fish to eat the bugs will work better than adding toxic chemicals which may harm your plecos.