flatworms

Are they rust colored? If so, they are probably red planaria and while they are a pest, they ultimately aren't that big of a deal.

It's easier to deal with them when you only have a few using Flatworm Exit though the recommended dosage is usually not enough to get the job done.

Six Line wrasses are also a good way to control them naturally.

-JB

 

Flatworm exit has done a good job for me. Just make sure that you siphon them out and run carbon shortly AFTER you are seeing them die en-mass. I have heard interceptor and pig-dewormer work pretty well also, though they ay be a little more difficult to acquire as both are veterinary products.

 

+1 wrasse, but I dont think you have to limit yourself to a sixline, I am pretty sure almost any wrasse will destroy these.

 

I've also seen Arrow Crabs eat them as well. And it is very fun to watch.

 

Flatworm Exit does do a good job but it's prohibitively expensive on a large tank. I've heard that yellow Damsels will some times eat them as well.