fast-acting solution for nuisance flatworms. Large, unchecked populations of flatworms create living mats that smother and deprive corals of food and light. Salifert Flatworm eXit works within 30 minutes for fast and effective relief of nuisance worms. Treat existing reef aquariums with flatworm infestations or use Salifert Flatworm eXit as part of a quarantine regimen before introducing new coral or live rock into your display aquarium. Remove dead flatworms after use and run activated carbon. Use 1 drop for every gallon. 10 ml bottle treats up to 300 gallons.