Flatworms reproduce quickly and can wreak havoc in an aquarium, causing infection and disrupting biological processes. Salifert's Flatworm Exit is a flatworm exterminator that is safe fishes and invertebrates, but use with care: flatworms produce toxic body juices when they die, so you must siphon as many out of your tank as possible before using the treatment.
Flatworms hide in crevices of rocks and corals, so use a powerhead or pump to help dislodge them and thoroughly circulate the treatment - in a smaller tank or quarantine tank, circulate water manually. Once you've removed as many flatworms as possible, use Flatworm Exit according to instructions, and then remove as many of the dead flatworms as you can. Then add approximately 1 pound of activated carbon for every 50 gallons to remove any remaining toxic juices. We recommend having water ready for a 25% water change as well.
Add one drop for every 4 liters or 1 gallon. Place drops in a high flow area of the tank to allow the treatment to spread throughout the tank. (If water volume is too low for a powerhead, circulate manually.)
Flatworm Exit should begin to work within 30 minutes. However if within 45 minutes no visible death of flatworms occurs add 50% more.
As soon as the flatworms start to die, use activated carbon to filter out toxic body juices.
After an hour or so you can turn any UV or ozone on again.