Flatworm exit

[syncro]

There are many species of flatworm, not all treatable with flatworm exit (or others).

You can buy a treatment and experiment on a few worms in a dish outside your tank.

[Scythanith]

I've used it successfully on a mixed reef multiple times. Have some water ready for a change, carbon ready to turn on after the FWE kills the FW's, and a fine net or siphon to take out the floaters. The longer you leave them in your tank the more they will degrade and release toxins.

And if you don't notice them releasing off the rocks in the allotted time, hit them with another full dose right away.