Flatworm Rx is an exceptionally fast, safe and effective treatment for flatworms in your reef or fish only saltwater aquarium. This innovative product prevents disruptions in the biological processes as well as coral degeneration caused by flatworms. The new potent solution reaches low flow areas between corals and behind rocks. This product contains no chemicals, antibiotics or pesticides. Reef Safe. Easy to Use. No Chemicals. No Antibiotics. Veterinarian Approved.