Sick Pleco

tiny thin worms!

We decided to do another tank change, and found tons of worms swimming around after giving the gravel a good cleaning. Hadn't seen these until today, and we'd been cleaning the tank alot since our pleco got sick. What are they? Can they harm fish.

I tried reading around to figure out what they are, but to no avail.

We decided to really clean the tank, and use quick cure, in hopes of killing the worms. Do you think it could have been the lettuce? I didn't microwave as long as that one post said, because it smelled like it was burning. Or perhaps the zucchini or the water sprite before that?

Could these have been what killed Black on White?

Thanks in advance for any help!

Here's a pic.

worms 013.jpg
 
look like nematodes to me - generally harmless but an indication of poor water quality.

edit : just read start of your thread - sorry 'bout your pleco :(
 
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