Planaria or detritus worms? Please read if you have been told you have planaria

Hi all,
I think you are right. A lot of the posts where people have failed to control their "Planaria" with chemicals like Fenbendazole (in "Panacur" etc.) is because they weren't Planaria (Platyhelminthes), but either Leeches or worms from the "Annelida".

I keep some flat slates in my tanks, and every couple of days I lift them up and look for Planaria and Leeches.

They are both "blobs of jelly", but if you put the slate in some water, the Planaria will move by "gliding", and the Leeches by "looping".

Black-worms, Tubifex and Detritus Worms are much more slender, and often swim with a rapid wriggling motion.

Most of the leeches you find in fish tanks aren't the blood sucking type, but general carnivores of anything small, meaty and fairly immobile (fish egg for example).

cheers Darrel

How do they enter the tank to begin with?

Great post Nat so many different types of worms and parasites it's hard some times to correctly identify ! I been there done that but now I just stay on top of a once every now and then safe dosage (like a full system quarantine) to keep my tanks completely parasite nematodes whatever can bloody harm my fish FREE LOL

Jackson said:

If you have one you have the other

Click to expand...

INCORRECT. Detritus worms are found in tap water. They can survive a lot. Certain treatments may kill off MANY of them, but they can QUICKLY repopulate a tank. Most importantly, detritus worms are in almost every source of water. Planaria are NOT.

Jackson said:

Planaria common name are mostly harmless as well. Different parts of the world have different planaria. That's why most vids on YouTube showing them go after shrimp are from Asia where predatory planarium are common.

Click to expand...

Also incorrect. There is ONLY ONE species of Planaria. There are no subspecies. There are many species of detritus worms and copepods, but ONLY one species of planaria.

Jackson said:

I read an article on pfk recently what a joke IMO just trying to scare shrimp keepers into buying useless products

Click to expand...

That's why it's important to realize what you actually have BEFORE you treat. Especially since treating for PLANARIA, when you actually have DETRITUS WORMS can result in a massive die-off and ammonia spikes. Remember I said treatments can kill off MANY? Detritus worms usually number in the hundreds very easily. Planaria are only found in very SMALL groups, but most of the time you'll see them by themselves.

Allfinsfishy said:

Great post Nat so many different types of worms and parasites it's hard some times to correctly identify ! I been there done that �� but now I just stay on top of a once every now and then safe dosage (like a full system quarantine) to keep my tanks completely parasite nematodes whatever can bloody harm my fish FREE LOL

Click to expand...

Be careful with that. Detritus worms, while often nematodes, are actually HELPFUL to an aquarium. They process waste and debris into smaller particles so that the bacteria can consume it easier.

foti said:

How do they enter the tank to begin with?

Click to expand...

Planaria or detritus worms?

Detritus worms are very incredibly common. And your city water may kill off a lot of them, but probably not all - and some eggs may survive the process as well.

Planaria are MOST commonly spread through live plants raised in outdoor environments and placed in aquariums.

Hi all,

Also incorrect. There is ONLY ONE species of Planaria.

Click to expand...

This is true for the genus Planaria, it now has only one species (Planaria torva), but there are hundreds of species of "Planarian" from different genera.

Common ones in the UK are Dugesia species.

Have a look at <Tricladida>, <Skeptical Aquarist: Flatworms> & <PFK: How to solve a problem like Planarians>.

cheers Darrel