Methods to Treat Flatworms in Your System

Share the knowledge

While the flatworm is considered the simplest of the worm groups, there is nothing simple about getting rid of them if you have an infestation. These pesky creatures reproduce at an alarming rate by simply splitting in two. There are no mating rituals and no eggs to hatch. When the flatworm splits, it immediately forms a new flatworm, and so on and so on, until you have thousands of flatworms in your system. This means that the flatworms may be feeding off of your fishes’ skin and eyes, so all of the fish in your system will eventually die.

A freshwater bath can help get rid of flatworms, but this is only a short-term solution. The flatworms will eventually return, whether it’s a few months or a few weeks later. A wide range of chemicals are available today to help combat flatworm infestation in systems, but many of them may fall short. Malachite green, which is banned in the U.S., and Paracide F (formalin 37%) are effective at killing flatworm infestations, but again, the effect is short-term, as the flatworms will keep coming back if even one is left behind. Copper has been shown to reduce the reproductive success of flatworms, but it doesn’t completely stop them from reproducing. That said, there is a treatment that seems to work long-term and it is attracting a significant amount of attention in the industry. It’s called Salifert Flatworm Exit.

When used correctly, Salifert Flatworm Exit should kill all flatworms. And according to tests and numerous consumer reviews, the flatworms will not return. To successfully kill flatworms, begin by siphoning out any flatworms in the system. It is important to siphon every area of the system including any crevices, which are excellent hiding places for flatworms. In some cases, consumers forget that flatworms may be hiding in crevices, so they neglect to siphon them out. This means that after “killing” the flatworms, you may notice that they “return” rather quickly. This is because some of them never left! It is recommended that you use a vacuum, turkey baster or powerhead to siphon out flatworms before and after treating the system. You must siphon out all dead flatworms following treatment because the flatworms’ body juices are toxic and can kill your fish.

Besides siphoning out as many flatworms as possible before treating your system, you should also keep sufficient fresh activated carbon in a canister ready and turn off UV, ozone and remove activated carbon. It is important to keep the skimmer turned on.

While Salifert Flatworm Exit is safe for most fish and invertebrates, it may have a corrosive effect on some sea animals. It won’t kill your sea animals or fish, but it can corrode the skin, which, of course, will regenerate eventually. For more details about how to use Salifert Flatworm Exit and information on how to purchase, visit Marine Depot at

About Flatworms

There are roughly 20,000 species of flatworms in existence today and they can be found just about anywhere in the world — either free living or parasitic (such as a tapeworm). Flatworms (Red Planaria) can be microscopic or several feet long. They are typically rust-colored and thin and it has no skeleton or formal respiratory system.


All About Worms is always free, always reader-supported. Your tips via CashApp, Venmo, or Paypal are appreciated! Receipts will come from ISIPP Publishing.

CashApp us Square Cash app link

Venmo us Venmo link

Paypal us Paypal link

Note: Some links on this site are partner links. That means that we earn a tiny bit if you purchase something through them, at no extra charge to you. This helps offset the cost of keeping this resource free for everybody (it doesn't cover our costs, but every little bit helps! :~) )

Share the knowledge

Author: The Top Worm

Leave a Reply

Your email address will not be published. Required fields are marked *