what are they?????

[paddyob]

Originally Posted by Aquattro

Flatworm exit will exit your entire tank unless you follow the directions carefully Flatworms are toxic, and when they die, they release the toxins into the tank. And not all fish can eat them, again, toxicity.

They aren't a nutrient thing that will go away. Try manually removing as many as you can, then try the suggested fish (some wrasses I think) to control them.

+1!!!

A spotted Mandarin will eliminate the issue.

I had a 20G overrun with them at one time.

I added a Spotted Mandarin and within two weeks the issue was gone.

I understand sixline wrasse might also enjoy them.

Flatworm Exit works... but never guaranteed to get them all... and you can bomb your tank.

Try natural first.