Molly Help

[Freshfishlove]

I got a new molly today and after putting him in my tank I realized his tail and anal(?) fins are a little split. Not only this but he is also kind of hovering funny. Sometimes he swims fine sometimes he hovers (twitches.)
I immediately put him into my little emergency tank and gave him some melafix.

Does anyone know what might be going on??

My biggest concern is it being something that could spread to my other fish (I also have 2 other mollies I bought from same store but they are in my main tank. Only alternative would be to put them in a bucket, but they seem healthy.

 

[Attenbruh]

The "On-his-side part" may be swim bladder. If so, feed him a boiled pea without the skin.

 

[Freshfishlove]

It’s more of a twitch-wiggle, he only ends up on his side for like a millisecond and it doesn’t happen often.

 

[Colin_T]

It's probably an external protozoan infection. Add some salt to all your tanks.

SALT
You can add rock salt (often sold as aquarium salt), sea 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.