Flatworms?

[TMF89]

Is that what I'm lucky enough to get to deal with? They don't seem to move much, and I can blow them off the rockwork with a baster. Thanks guys!

 

[DenverSaltyFarm]

I had a 120g like that. Flat worm rx completely killed them all without nuking my tank. Just do what the directions say and do 1 treatment then another 2 weeks later to kill anything that hatches from egg

 

[Ehder]

Yep agreed with the above comment. Those do look like flatworms, although not the bad kind. I've had success with prazipro which is display tank safe and other forms of dip methods (bayer insecticide or iodine dip) which are not for the display.

 

[ThisIsTheWay]

Agreed, looks like red planaria. Some of my rocks look similar and I was hoping for a natural solution but I'm starting to lean towards chemical eradication if it goes on too long.