Round platy

[Robbos]

I have a tank with platy in. They all seem healthy and are eating but one is really round. I feed them mostly good quality dried food but also daphnia and blood worms. There are only 6 of them and they’re all females.

 

[Colin_T]

What does the fish's poop look like?

If the fish is eating well it could be full of worms. Common livebearers like platies are regularly infested with thread worms and should be treated as soon as you get them.

Intestinal Worms like tapeworm and threadworms normally 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.

 

[Robbos]

Thanks for all that information, I will certainly try it. I have ordered the medication and will follow the instructions in relation to water change
The fish continues to swim and eat but I’ll keep an eye on her

 

[Robbos]

Could parasites still be the cause if there are no new fish in the tank? Sorry I’m a novice

 

[Colin_T]

Fish regularly carry intestinal worms and they have them at the fish farms before being sent to other countries.

If a fish bloats up overnight and stops eating, it has an internal infection and will probably be dead within 24 hours. They usually sit at the surface or by a filter outlet gasping.

If a fish gets fat over a period of months, it can be an internal growth/ tumour and there is no cure for that. You leave the fish until it stops eating or can't swim properly and then euthanise it.

The most common cause of livebearers (platies mollies, guppies, etc) becoming fat is pregnancy, but they don't normally look like the fish in the picture. Deworm the fish and see how they look in a month. If it's still fat like that in a month then it has a tumour or cyst.