Bad Guys
Bad Guys

First thing to note: These are not welcome in your tank, if you see them, time to take action!

Flatworms come in a range of colours, species, threat levels, swimming varieties, and some can look so exotic that you may secretly wish for an infestation. The Leopard Polyclad Flatworm, is not a species you would wish for in your aquarium.

There are many types of flatworm that can be found in the marine world, but the Leopard Polyclad Flatworm that will dine on your snails and clams. These pests should be removed as quickly as possible.

Flatworm on Coral

Leopard Polyclad Flatworms are generally considered easier to deal with than Acropora Eating Flatworms as their diet is more limited. They specialise in snails and clams, which means once you have no snails or clams left in your system, the worm will eventually starve and die. Take caution if you plan to starve them out, these worms can be incredibly resilient & resourceful, it is likely to take several months of having no clean up crew to starve it out!

Leopard Polyclad Flatworms are not considered to be prolific breeders, often a system will only host one or two of these pests at any given time.

The predatory flatworm species can grow to be as large as a human hand, or can be as small as a pin head when first born, which is why getting rid of them can be so difficult. They can be incredibly difficult to spot.

The most common flatworms come in shades of brown, grey and beige, some carry a spotted, leopard like pattern.

How do you control the numbers?

polyclad flatworm
polyclad flatworm

The offence is a good defence when it comes to Leopard Polyclad Flatworms. Dip all corals before putting them into your aquarium, and where possible, quarantine them and monitor them for at least three weeks before putting them into your main display.

If you have found them in your main display, remove them manually. Where you can’t catch them, remove the entire rock in your display tank and treat it with a dip until the worm is removed.

Another way to catch them is to potentially set a trap for them using live clams, though this can prove to be expensive.

Do they have any predators?

Unfortunately no. Leopard Polyclad Flatworms normally grow too large for wrasses and other predatory species of fish. Manual removal is your only option.


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