Platys in Quarantine

[Fox46]

I bought five Platys (one male 4 females) four weeks ago from an LFS I don't usually use. I put them in a 25l quarantine tank (thankfully) and settled in to observe them. I immediately noticed they were trailing long white poo, and I mean long. I suspected stress and change of diet, so waited. One female died after about three days. The poo became occasionally darker, sometimes multi shaded, but remained trailing. After 3 weeks I thought maybe internal parasites so gave them a dose of eSHe ndx four days ago and did a 50% water change. They stopped doing trailing poo, some of it is still white though not as bad, but now another one died yesterday. She'd been listless and not eating, hanging around at the bottom or lingering motionless at the top for a couple of days. I've checked the water parameters three times, all normal. I regularly hoover up the bottom of the tank, I feed a varied diet of flakes, granules, veggie granules and bug bites. From time to time I notice they have clamped fins, but then they seem okay again. For 24 hours now the male has been bothering one of the females and lunging at the other, causing it to hide from time to time. I notice all have clamped fins this morning.
I'm at a loss now. I have a follow up eSHe treatment planned for next week to catch any eggs but I'm just not confident about putting them in with my other fish. Anyone any ideas?

 

[Colin_T]

The male that is harassing the female and bullying the other male is dominating them and wants to be in charge. He sees the other male as a competitor and will harass him until he submits or dies.

--------------------
The clamped fins can be from poor water quality, chemicals in the water, or external protozoan parasites. Salt can help, as can big daily water changes for a week. See below for info on salt.

--------------------
The following link has info on stringy white poop in fish. Your fish probably still have intestinal worms and you need several treatments to get rid of all of them. The first dose usually kills the adult worms but more can hatch from eggs in the fish and these need to be treated too.

Make sure you remove carbon from filters before treating otherwise the carbon will remove the medication.

What to do if your fish has Stringy White Poop.

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...

www.fishforums.net

--------------------
SALT
You can add rock salt (often sold as aquarium salt) or swimming pool salt to the aquarium at the dose rate of 1 heaped tablespoon per 20 litres of water. If there is no improvement after 48 hours you can double that dose rate so there is 2 heaped tablespoons of salt per 20 litres.

If you only have livebearers (guppies, platies, swordtails, mollies), goldfish or rainbowfish in the tank you can double that dose rate, so you would add 2 heaped tablespoons per 20 litres and if there is no improvement after 48 hours, then increase it so there is a total of 4 heaped tablespoons of salt per 20 litres.

Keep the salt level like this for at least 2 weeks but no longer than 4 weeks otherwise kidney damage can occur. Kidney damage is more likely to occur in fish from soft water (tetras, Corydoras, angelfish, Bettas & gouramis, loaches) that are exposed to high levels of salt for an extended period of time, and is not an issue with livebearers, rainbowfish or other salt tolerant species.

The salt will not affect the beneficial filter bacteria but the higher dose rate (4 heaped tablespoons per 20 litres) will affect some plants and some snails. The lower dose rate (1-2 heaped tablespoons per 20 litres) will not affect fish, plants, shrimp or snails.

After you use salt and the fish have recovered, you do a 10% water change each day for a week using only fresh water that has been dechlorinated. Then do a 20% water change each day for a week. Then you can do bigger water changes after that. This dilutes the salt out of the tank slowly so it doesn't harm the fish.

If you do water changes while using salt, you need to treat the new water with salt before adding it to the tank. This will keep the salt level stable in the tank and minimise stress on the fish.

 

[Fox46]

Thanks for that very comprehensive response. A lot to think about there. Where would the external protozoan parasites (which I'm assuming the salt treatment is for) have come from? This was a sterilised quarantine tank that hadn't been used for 9 months or more, and there are no fish other than the 5 (now three) that I bought in there.

 

[Colin_T]

All fish tanks have microscopic organisms in, including bacteria, fungus, protozoa and viruses. When you got fish from a pet shop, these microscopic organisms would have been on the fish or in the water and they get transferred into your tank by the fish or water from the shop. Initially the numbers are low but over a few weeks they build up in quantity and eventually start to infect the fish.

Yes the salt is to treat the external parasites/ disease organisms that are potentially on the fish. the salt won't hurt the fish but it should kill any nasty parasites infecting the fish.