You need a picture on the back of the tank and some plants and caves for the fish to feel more secure.
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What is the GH (general hardness) and pH of your water supply. This information can usually be obtained from your water supply company's website or by telephoning them. If they can't help you, take a glass full of tap water to the local pet shop and get them to test it for you. Write the results down (in numbers) when they do the tests. And ask them what the results are in (eg: ppm, dGH, or something else).
Livebearers (platies, guppies, swordtails, mollies) need water with a pH above 7.0 and a GH above 200ppm for platies, guppies and swordtails. And a pH above 7.0 and a GH above 250ppm for Mollies.
Rams come from soft acid water with a pH below 7.0 and a GH below 150ppm.
If you keep mollies in soft water with a GH below 200ppm, they end up having lots of issues.
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The molly probably has intestinal worms, which can be treated with Praziquantel and Levamisole. If these are not available, then look for Flubendazole.
However, you should treat for whitespot first because this is more dangerous and spreads faster.
To treat the fish for whitespot, simply raise the water temperature to 30C (86F) and keep it there for 2 weeks.
Increase aeration/ surface turbulence when raising the temperature or using medications, to maximise the oxygen levels in the water.
After the whitespot has been treated, then treat for worms.
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Fish do a stringy white poop for several reasons.
1) internal bacterial infection causes the fish to stop eating, swell up like a balloon, breath heavily at 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.
An internal bacterial infection is unlikely to be the problem.
2) internal protozoan infection 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.
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, handle with care, don't inhale the medication, and wash hands with soapy water after treating the fish or working in the tank.
An internal protozoan infection is unlikely to be the problem.
3) intestinal worms like tapeworm and threadworms cause the fish to lose weight, continue eating and swimming normally, do a stringy white poop. Fish can do this for months and not be too badly affected. In some cases, fish with 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 Levamisole to treat thread/ round worms. If these medications are not available, look for Flubendazole and use that instead.
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 3-4 weeks. The first treatment will kill any worms in the fish. The second and third treatments kill any baby worms that hatch from eggs inside the fish's digestive tract.
You do a 75% water change and complete gravel clean 24-48 hours after treatment. Clean the filter 24 hours after treatment too.
Treat every fish tank in the house at the same time.
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 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.
