Planarian eaters

Flatworms in reef aquariums are quite common pests. These flatworms, often reddish-brown in color, sometimes arrive as stowaways with a coral or live rock, but there are solutions to eliminate them (that's the good news). Several species of marine fish eat flatworms, particularly against the species Convolutriloba retrogemma, but also other worms (beware of feather duster worms). Note that the more mature the fish, the more effective they are. If you prefer a chemical rather than a biological solution, you can use a treatment for corals. It is also possible to manage other unwanted organisms with an anti-aiptasia treatment or an anti-cyanobacteria treatment.