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Planarias in my tanks

I emptied some of my Neo tanks to clean them as with some tanks i had problems with Planaria. Introduced with some mosses that i got from a friend. What impressed me is that i have Neos split up in colors in some tanks..red,blue and yellow…and i found out that the planaria ( about 60% of the populations have a similar color..wierd) You are what you eat ;-(
Attached article that Ulli Bauer wrote for Breeders and keepers Vol III and i hope this will help you to handle Planaria.

Help!!! Planarians in my tank!
by Ulli Bauer

It does not have a really good reputation, especially amongst shrimp and fish breeders – the planarian flatworm. In a normal social tank you don’t see these worms very often, and if you happen to spot some, their number is usually very low. Planarians tend to lead a very secretive life in the presence of potential predators. However, if there are none of those in the tank they come out during the day, too, and often in impressive numbers.

There are many different planarian species, and not all of them are dangerous for invertebrates – however, there are quite a few that are. People even have observed hitherto harmless planarian populations to suddenly turn predatory, with a ravenous appetite e.g. for shrimp. Young fish, especially the larvae that are still on the ground, are always in danger of being eaten by these flatworms, and there are breeders who credibly claim that planarians “helped” them get rid off all the young fish in their breeding tanks very efficiently. Planarians also love eating snails, and you will often find them inside the mantle tissue under the snail shell where they take shelter – bed & breakfast for flatworms, quite literally.
However, all planarians have the same internal anatomy, which discerns them from all other worms. Their mouth opening is not in their head (where you would search for it first, now wouldn’t you?), but in the middle of their body on the ventral side. Starting there you will see a Y-shaped intestine, whose one arm stretches from the mouth opening towards the head, and whose double arms go from the mouth opening towards the rear end.
This Y-shaped intestine is well visible when you use shine-through light to look at your planarian, and it makes identification very easy.

Now we have identified our worm as planarian – but what do we do now we know? Please do not give in to your first reflex to just squish it. Planarians have many undifferentiated stem cells, which gives them a regenerability that’s in fact legendary. An entire new worm can grow from just a shred. Thus, by squishing you will not solve the problem, you will aggravate it! Science has found that planarians can memorize knowledge they gained (e. g. that a shrimp is good food) in a way that allows them to pass it on when reproducing by division. Every new planarian generated from a part of the worm that gained the knowledge is also in possession of this knowledge. All of this makes planarians highly interesting worms … if they only didn’t snack on fish larvae and sometimes go after snails, shrimp and small crayfish.
However, you will need the utmost patience to remove all planarians with any of these methods, and if you apply yourself just one bit less you will end up with a considerably smaller amount of planarians, but they won’t go away entirely. If you want to make absolutely sure you zap all the worms in your tank you ought to consider the use of an anti-worm drug from veterinarian medicine. Treatments with garlic, electricity and so on have not proven to be efficient or can even be dangerous. The anthelmintics Panacur and Flubenol help, however, they are deadly for some (Panacur) or practically all (Flubenol) snail species in the aquarium. As these drugs are available only on prescription in many countries you ought to get them from your veterinarian. They are not approved for aquarium use (which may lead to discussions with your vet, be prepared), and for this reason, there is no officially recommended dosage for the use in a tank with inverts or fish. In the net you’ll find various dosage recommendations that were conceived on the principle of trial and error. All of them work quite well, actually. When in doubt, choose the somewhat higher dosage in order to avoid the generation of resistances, and remember to treat again after two weeks in order to zap new planarians that may have hatched in the meantime, before they can lay eggs in turn.

Also keep in mind that many aquarium snails do not tolerate Panacur, and that Flubenol is deadly for practically all of them. The drugs do not differentiate between snails and planarians, as their enzymatic structure is comparable. When treated with Panacur or Flubenol, the animals affected starve to death as their digestive enzymes are deactivated. Thus it takes a few days until you see the effects of any anthelmintic. Both drugs do not dissolve in water but settle in the aquarium ground, where they will remain for a very long time if not removed. It may take one to two years before you can keep snails in such a tank again. Larger doses of Panacur may lead to deformations in shrimp and to molting problems, and the reproductive rate of the shrimp may be reduced significantly. Meanwhile, some non-prescriptive anti-planarian drugs are available in trade, too. However, please do not use them carelessly either. Most of them are based on extract of betel nut, which may be carcinogenic. Thus you ought to make absolutely sure your aquarium really has planarians and not some other kind of worm before you start treatment.

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