Planaria Or Detritus Worms? Pet of the Month
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Fish Herder
Mar 6, 2014
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US it seems I may have went from one problem to another one!!! I'm not sure what these little white, thread like worms are. They are very tiny! And my betta is having some issues as well(though I noticed this before I noticed the Hydra that I just dealt with! betta's fins are getting a bit ragged. And I keep seeing him get a spot around his head/mouth every so often. It's only one spot, almost similar in appearance to ich(but it's not ich) and after two of three days it disappears.

Also, my three nerite snails are hanging out ABOVE the water line in the flow of the spray bar(so they are still wet). I have a picture of two as one snail was out and about but he just went back up there.

Something is bothering my guys!!! Please help! I have attached pictures.

Just some additional info...i did kill hydra with hydrogen peroxide. Betta and snails were not in tank. But it did kill almost all of my plants. Thankfully they are beginning to grow back though so that's why his tank seems so sparse. Oh and very rarely does he miss his omega one betta pellets. So this isn't due to uneaten food. I just did a 50% water change on Thursday. I vacuumed it out real well and pulled some dead plants out then too.

Finally, here are the pictures!!

Tank pic

Aidan's pic of fins(you can also sort of make out a worm that is on the glass in front of him.

Aidan not wanting me to take a pic of the sorry..he's such a character!! Lol.


Best picture of worm I could get.

If these truly are can I get rid of them?? Obviously something is bothering my betta and the snails. Any help is appreciated!
Planaria itself isn't harmful to fish, the fish may even eat them! the (maybe) problem is you may have poor water quality which allowed them to flourish in the first place. Best thing is to reduce feeding and do weekly 30% water changes (although it may be stressful) . with a sand substrate it looks like, when you do water changes stir the sand up, this is to ensure no food or detritus is in any sand pockets. after a few weeks of doing this, your issues should be gone.
Please read my post is not over feeding. I feed him once a day with 4 or 5 pellets. Or twice a day 3 pellets each. He eats everything most days. Very rarely one pellet will fall that he doesn't see. I only feed one pellet at a time to make sure he eats them.

I just did a 50% water change Thursday stirring things up really well due to decaying plant matter.

The quality also isn't an issue. I forgot to add that to my last post. This was done before the water change.
Nitrate-5 or 10(can't remember....tested three tanks but it was one of these. Lol.)

And yes...some planaria ARE harmful. They are predators. Some leave fish alone and some don't. I just wanted confirmation on if I'm right and possibly how to get rid of them.
I would just keep vacuuming it and doing the 30% <-- water changes rather than 20 weekly. and scrub the sides of the tank well.

For one may want to read this article.

For another....actually read my posts!! I just said I'm doing 50% water changes! Not 20! Please pay attention. I'm not trying to be mean....but also please dont just google a problem someone has and post the first thing on there. (I looked up how to get rid of planaria and another forum had a post that yours matched very well.) Not everything on Google can be relied on, hence for coming here for good information from experienced members.

Obviously something is wrong with my tank. My betta isn't quite right and the snails aren't acting normal. Does anybody else have any good information?
I have always found that when ever snails or shrimp start making for the surface and modes of escape there is something wrong with the water, this rule does not necessarily apply to Apple/ Mystery snails since they will leave the water to lay their eggs above the water surface. When ever you notice your usual tank inhabitants acting oddly or out of the norm generally a water change is needed to help re-stablise the water paramaters. Of course there is always the chance that there is a problem with your source water (tap) and adding more source water may just make your tank situation worse. However if you are using a dechlorinator/ water ager this should not be an issue.
Some other factors that can throw a tanks water out of nice living range for tank inhabitants is aerosol sprays, this could be obvious fly/ spider killer type sprays that are designed to be poisonous, down to air freshner type sprays that are supposed to maker your house/ room smell nice right down to aerosol deoderants and hair sprays that might have been applied near the tank. No normal tank tests will show the possible contamination from such aerosols but always something to consider as a possible reason for the change in the snails behaviour. A  case in point  a neighbour of mine had some fish in their loungeroom and they had complained that every day more fish where dying. I ran through all the possible causes and came up negative. Then when I was in their house I saw a self timing aerosol sprayer for air freshner that was meant to go off every couple of hours. Once they got rid of the spray air freshner no more dead and dying fish. Something else that many people don't realise is poisonous is TEFLON (you know that nifty non-stick stuff they put in fry pans etc), the fumes from TEFLON has been known to kill birds that have been exposed to the fumes.
If your source water is coming up as good, then my best suggestion would be to continue the water changes, perhaps a smaller amount more frequently might also be needed, especially if the tank is quite small e.g.20L.
The other reason the nerite snails may have left the water is that they are actually running out of food. Nerites are avid eaters of algae and biofilm and if there is not a lot available they can in starve.
As for the worm type things it is very hard to actually see which critter they are, either detruis worms which generally are not a huge issue or planaria which can be an issue. I would however usually expect a Siamese fighter to eat planaria. If you really do suspect planaria then you can buy planaria traps, I am not sure how well they actually work but a better and safer option then any chemicals to kill them.
BettaBettas said:
"Any help is appreciated!"
Actual help. I'm glad you want to do research. That's a good thing. When I first got here, other than asking some questions, I just lurked around and read a ton of stuff. I didn't post much to anybody. I didnt know much then. I'm only recently starting to try to help certain people from having been through stuff with my tanks. So...if you don't really tip is to sit back and learn. You can do research still as long as you want. But you have to remember that there is a bunch of misinformation out there to wade through. So a "quick search" may not be a good thing and could be detrimental in certain situations. Hope these tips help.

Now, back to the topic...

Thanks for the reply Baccus. These are nerite snails so while I know they go above the water line at times, this is a bit much. I will double check my water tests both tank and tap in the morning. How many minutes would I shake the tap water up to make sure it's gassed out properly?

Also, I did just start using the api tap water conditioner, one drop per gallon(of changed water of course). There are no sprays at all of any kind in this room. So other than the melting plants that I had to deal with from the hydrogen peroxide treatment, the water should be good.

If this is a food thing for them....what can I put in there? Will they eat cucumber? I also was thinking of putting in an Indian almond leaf as well to maybe help with the betta since I don't know what the cause is. Will the snails eat on the leaf once it sinks and starts to decay?

One more question....i had read a couple of things saying that aquarium salt can kill planaria, is this true? It was either one teaspoon per gallon or one tablespoon per five(why it was said this way I don't know. Lol. I would stick with one tablespoon per five gallons- added slowly over a few days - if you think this could be helpful? I do have api general cure but hate to use it on anything small since the packet size is for 10 gallons. Hard to measure and I don't know for sure what these things are.

Looks like planaria to me, because of the head shape.
When I had Planaria in my shrimp tank I used a product called No Planaria, got rid of them in 3 days, didnt harm shrimp or my Betta.
Please Note.
No Planaria WILL kill your snails.
That's what I was thinking Nick but I'm not sure I want to use that stuff. Didn't you say when you used it and afterwards you did water changes and carbon for a bit that it still stuck around and killed the snails?

Also, do you think it could be causing the cyst like things on my betta as well? The spots that look like ich and then fall off a few days later?(one spot at a time shows so it's not ich for sure)
To try and make any chlorine  gas off from the water you are going to add I do not know if there is a set time frame so to speak, since the levels of chlorine will be different depending on the hardness/ softness of the water and if your water supplier has had any issues with their water/ or storage.
For example when we where having a heatwave and there had been no rain for months people where using water quicker than the towns resivours could supply it, and the system that the water supplier (FRW) used to apply chlorine relied on the water in the resivour tanks being a certain height and so much chlorine was injected at set times. With the water being lower in the tanks the water was in effect being over treated with chlorine. This resulted in you actually being able to smell the chlorine as it came out of the tap. A lot of people didn't realise there was an issue and accidently killed/ poisoned their fish when carrying out water changes. Therefore on the majority of my tanks I always smell the water coming out of the hose first before deciding on doing water changes, and if I can not smell obvious chlorine I go ahead. When adding the water from the hose I have the hose nozzle on shower, this breaks up the water giving the water more surface area so hopefully some chlorine will gas off. For my native shrimp and spotted blue eye tank I will pre-age the water, putting the water in a large tub with de-chlorinator and then adding an airstone. The shortest time I have left this water bubbling prior to a water change has been 4 hours the longest has been a week or more. Personally I am inclined to go with as long as possible before using this water.
If your using a jug or something similar to add your water to the tank, in order to get the same effect as using the shower option on the hose nozzle you could pour the water through an upside down colander/ strainer. And pour from a bit of a height so that the water has more time exposed to the air before it reaches the tank.
In the tank are you running the filter with charcoal? If not some activated chlorine in the filter might help remove what ever is upsetting the snails, it might also help remove any left over hydrogen peroxide. Seachem purigen might also be worth investing in for this purpose.
I don't think zuchinni or cucumber will interest nerite snails, when I have needed too I have given my nerites Nori sheets, which are the seaweed wraps that are used around sushi wraps. Alternatively you could try leaving some rocks out in a container of water in the full sun to encourage algae growth which the snails will happily eat. You can keep a few rocks on the go so once the snails have "cleaned" the first rocks you can add more that have been growing algae in the mean time.
After the hydrogen peroxide, I did an almost 100% water change(lost suction when it was an inch or so off the sand, couldn't get it back). I had cleaned the filter, dumped it and rinsed well too. Then I ran carbon in the filter for almost a week to make sure before putting them all back in the tank. Also, I don't have chlorine as I'm on well water. I just know Byron always says to either shake the tap water briskly for some time or to let it set for 24 hours before testing it. I just want the tests to be accurate is all. I wasn't sure if this counts with water that has no chlorine.

One problem with leaving water out right now is mosquitos...Guh. and I'm not sure if the rocks I have are safe to out in the tank. I haven't tested them yet. They were going to be for my big tank when I get that done.

I guess I'll do some research on feeding them just in case. But will they eat stuff off the almond leaf when it starts to decompose like some baby fish do?

And would the aquarium salt be worth a try at all?
Didn't you say when you used it and afterwards you did water changes and carbon for a bit that it still stuck around and killed the snails?
Yes, 3 or 4 weeks latter snails still died.
Also, do you think it could be causing the cyst like things on my betta as well?
I will say this when my tank had planaria while I did not notice what you describe in regards to the spot/cyst thing, My Betta did act strange, withdrawn not keen on eating and he did a lot of jumping.
Aidan is still eating though sometimes he has trouble seeing the pellet so I have to stick my finger in the tank and move it towards him. Sometimes even then it still takes a while. Other than that i haven't noticed any odd behavior other than he doesn't want to flare at the mirror as much. But then again he never did it a whole lot. He actually recently had Popeye too. I believe I saw the Hydra appearing after this as I couldn't figure out what caused it. I thought that maybe he just got stung in the eye from them. As for these cyst things...if another one shows up I'll get a picture. His lip is starting to look a tad off to me to. The last one I saw almost looked like it popped a bit when I was watching and part of it came off. Then the rest came off a day later or so. Sometimes I almost think I see a hairlike thing on him but I'm never sure because he just won't hold still and it's hard for me to focus clearly sometimes.

Another weird thing is....i think these came in on some water lettuce and/or water sprite that I re recently bought. I had introduced the plants to his tank and to my 20 gallon. I havent seen these things or any hydra in that tank at all! And I have a ton of copepods all over the place too in that tank. You would think I would see them!

I know next time I get plants it's straight into an alum bath for a few hours before going into the tanks!
Here is a little article that is about planeria - its from a rival site but it explains thing fairly nicely and its written by
How to Solve a Problem Like Planarians
And this link may help in how to get rid of planeria -
Killing Planaria & Hydra with Fenbendazole
Now, i have to say, i have tried the method of getting rid of planeria when i had a 3 gal snail tank and got these unsightly worms in the hundreds :x
Overfeeding was why i got these (its hard to know how much to feed snails :p )
Panacur dog worming tablets contains febendazole, so thats what i used and I crushed half a tablet and tried to dissolve as much as i could in tepid water and added it to the tank, its totally harmless for the snails btw. I had to do this treatment twice to get rid of ALL the planeria but it does leave a mess of white powder and dead planeria everywhere in the tank, i do mean EVERYWHERE.
So over the course of the next 4 weeks or so,  I forget how long it took tbh, but I slowly managed to get the tank back to looking somwhat normal by gravel vacs and cleaning leaves and decor as go along. Do not try to clean everything at once, it does go away eventually.
I was very hesitant in using hydrogen peroxide and in the end i decided against this as heard too many conflicting advice about that, am still not sure, I am one of those people who say that 'if in doubt, don't use!'
Now, nerites, as lovely as these snails are, they are truly hard to feed, especially if wild nerites. They will pretty much not eat anything else apart from certain types of alage, namely green spot algae.
I have had two nerites snails, a tracked zebra and a horned nerite, and i am sad to say they died, likely from starvation despite my best efforts to get them to feed on clear plastic left in water and had alage growing on that but was too late :sad:
I did try algae wafers, sinking pellets etc all to no avail. So as much as i like these snails, I won't get them unless am sure I can cultivate enough algae to feed them.
Baccus has given lots of good advice re these snails, the seaweed wraps and perhaps aramanth leaves would perhaps do the trick but am not 100% if this is enough for these snails.

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