What to do if your fish has Stringy White Poop.

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Colin_T

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Fish do a stringy white poop for several reasons.
1) Internal Bacterial Infections causes the fish to stop eating, swell up like a balloon, breath heavily at the surface or near a filter outlet, do stringy white poop, and die within 24-48 hours of showing these symptoms. This cannot normally be cured because massive internal organ failure has already occurred.


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2) Internal Protozoan Infections cause the fish to lose weight rapidly (over a week or two), fish continues to eat and swim around but not as much as normal, does stringy white poop. If not treated the fish dies a week or so after these symptoms appear. Metronidazole normally works well for this.

There is a medication (API General Cure) that contains Praziquantel and Metronidazole.
It's interesting that API and the Californian government have listed Metronidazole as a carcinogen. That's a concern considering it was widely used to treat intestinal infections in people.

Anyway, if you use this or any medication, handle with care, don't ingest or inhale the medication, and wash hands with soapy water after treating the fish or working in the tank.


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3) Intestinal Worms like tapeworm and threadworms cause the fish to lose weight, continue eating and swimming normally, and do a stringy white poop. Fish can do this for months and not be too badly affected. In some cases, fish with a bad worm infestation will actually gain weight and get fat and look like a pregnant guppy. This is due to the huge number of worms inside the fish.

Livebearers like guppies, mollies, swordtails & platies are regularly infected with gill flukes and intestinal worms. If the fish are still eating well, then worms is the most likely cause.

You can use Praziquantel to treat tapeworm and gill flukes. And use Levamisole to treat thread/ round worms. If you can't find these medications, look for Flubendazole, which treats both lots of worms.

In the UK look for:
eSHa gdex contains praziquantel that treats tapeworm and gill flukes.
eSHa-ndx contains levamisole and treats thread/ round worms.
NT Labs Anti-fluke and Wormer contains flubendazole.
Kusuri wormer plus (contains flubendazole) - sold mainly for discus, comes as a powder which is quite hard to dose in smaller tanks
Sera nematol (contains emamectin)

Remove carbon from filters before treatment and increase aeration/ surface turbulence to maximise oxygen levels in the water.

You treat the fish once a week for 4 weeks. The first treatment will kill any worms in the fish. The second, third and forth treatments kill any baby worms that hatch from eggs inside the fish's digestive tract.

Treat every fish tank in the house at the same time to prevent cross contamination.

You do a 75% water change and complete gravel clean 24-48 hours after treatment. Clean the filter 24 hours after treatment too.

Do not use the 2 medications together. If you want to treat both medications in a short space of time, use Praziquantel on day one. Do a 75% water change and gravel clean the substrate on day 2 & 3. Treat the tank with Levamisole on day 4 and do a 75% water change and gravel clean on day 5, 6 & 7 and then start with Praziquantel again on day 8.

The water changes will remove most of the medication so you don't overdose the fish the next time you treat them. The gravel cleaning will suck out any worms and eggs that have been expelled by the fish. Repeating the treatment for 3-4 doses at weekly intervals will kill any worms that hatch from eggs. At the end of the treatment you will have healthier fish. :)


---------------------
Thanks to essjay for providing the information about deworming products available in the UK. :)
 
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My discus have stringy white poop, what should I do first?
I just bought Flubendasol and Metro from the store.


Note; We don’t have Praziquantel and levamisole here.
 
Flubendazole does the same thing as Praziquantel and Levamisole. It kills all intestinal worms.

If the discus are eating well, use the Flubendazole.
If the discus is not eating well and has stringy white poop, use Metronidazole and after 2 weeks, use Flubendazole.
 
I can’t find flubendazole, praziquantel and levamisole anyone of my discus is super skinny and seems to be almost die.

I feed them bloodworm and they doesn’t seems to gain weight.

What should I do?

@Colin_T
 
Stringy white poop is nearly always worms (Capillaria). If you’re in the UK Sterazin works very well.
 
Looks like he's in Thailand - you might have to get these drugs from a veterinarian or a doctor. A lot of animals get worms.
 
Interesting replies, my fish get stringy white poop when they are constipated. I'm a little freaked out by all these people telling you to put so many chemicals in your tank.
If they were simply constipated, they wouldn't be pooping at all, would they?
 
I will suggest you read this before you decide to put medication in all your tanks. Not saying the above isn’t correct but I think we should also know the other possibilities for white poop that don’t require such drastic medication before making a decision.
 
Interesting replies, my fish get stringy white poop when they are constipated. I'm a little freaked out by all these people telling you to put so many chemicals in your tank.
brilliant
 
Not true.

Constipation means not being able to poo, so it is actually true.
Stringy white poo is a symptom of either a bad diet/something they ate, or certain infections such as Capillaria (the usual cause) or Hexamita. Constipation is caused by a blockage in the digestive system, which usually means a bad diet over a long period, although a single meal/food or an inedible item can cause it.

Both of these symptoms need to be cured...
 
Last edited:
Fish do a stringy white poop for several reasons.
1) Internal Bacterial Infections causes the fish to stop eating, swell up like a balloon, breath heavily at the surface or near a filter outlet, do stringy white poop, and die within 24-48 hours of showing these symptoms. This cannot normally be cured because massive internal organ failure has already occurred.


-----
2) Internal Protozoan Infections cause the fish to lose weight rapidly (over a week or two), fish continues to eat and swim around but not as much as normal, does stringy white poop. If not treated the fish dies a week or so after these symptoms appear. Metronidazole normally works well for this.

There is a medication (API General Cure) that contains Praziquantel and Metronidazole.
It's interesting that API and the Californian government have listed Metronidazole as a carcinogen. That's a concern considering it was widely used to treat intestinal infections in people.

Anyway, if you use this or any medication, handle with care, don't ingest or inhale the medication, and wash hands with soapy water after treating the fish or working in the tank.


-----
3) Intestinal Worms like tapeworm and threadworms cause the fish to lose weight, continue eating and swimming normally, and do a stringy white poop. Fish can do this for months and not be too badly affected. In some cases, fish with a bad worm infestation will actually gain weight and get fat and look like a pregnant guppy. This is due to the huge number of worms inside the fish.

Livebearers like guppies, mollies, swordtails & platies are regularly infected with gill flukes and intestinal worms. If the fish are still eating well, then worms is the most likely cause.

You can use Praziquantel to treat tapeworm and gill flukes. And use Levamisole to treat thread/ round worms. If you can't find these medications, look for Flubendazole, which treats both lots of worms.

In the UK look for:
eSHa gdex contains praziquantel that treats tapeworm and gill flukes.
eSHa-ndx contains levamisole and treats thread/ round worms.
NT Labs Anti-fluke and Wormer contains flubendazole.
Kusuri wormer plus (contains flubendazole) - sold mainly for discus, comes as a powder which is quite hard to dose in smaller tanks
Sera nematol (contains emamectin)

Remove carbon from filters before treatment and increase aeration/ surface turbulence to maximise oxygen levels in the water.

You treat the fish once a week for 4 weeks. The first treatment will kill any worms in the fish. The second, third and forth treatments kill any baby worms that hatch from eggs inside the fish's digestive tract.

Treat every fish tank in the house at the same time to prevent cross contamination.

You do a 75% water change and complete gravel clean 24-48 hours after treatment. Clean the filter 24 hours after treatment too.

Do not use the 2 medications together. If you want to treat both medications in a short space of time, use Praziquantel on day one. Do a 75% water change and gravel clean the substrate on day 2 & 3. Treat the tank with Levamisole on day 4 and do a 75% water change and gravel clean on day 5, 6 & 7 and then start with Praziquantel again on day 8.

The water changes will remove most of the medication so you don't overdose the fish the next time you treat them. The gravel cleaning will suck out any worms and eggs that have been expelled by the fish. Repeating the treatment for 3-4 doses at weekly intervals will kill any worms that hatch from eggs. At the end of the treatment you will have healthier fish. :)


---------------------
Thanks to essjay for providing the information about deworming products available in the UK. :)
How would one confirm it’s a worm? Remove & examine?
 

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