Unknown Molly fish deaths

[TO KYO]

I’ve been losing my fish one by one. Water quality is good and temp is 80. What I noticed is their face is losing color or missing scales.
(2nd)
(1st)

 

[Salty&Onion]

Your temperature is too hot for mollies. What are your exact and current water parameters? Mollies are also hard water fish and if you have soft water, don't expect them to be healthy and happy.

 

[JuiceBox52]

What is your GH? You should be able to find this info on your local water providers website or by calling them directly. Mollies need a gh of at least 250ppm, or they will be dying a slow death in soft water

 

[Colin_T]

You can add rock salt (often sold as aquarium salt), sea salt or swimming pool salt to the aquarium at the dose rate of 2 heaped tablespoon per 20 litres of water.

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 4 heaped tablespoons 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, 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 will affect some plants. The lower dose rate will not affect plants.

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.

Make sure your GH is high enough for them.

 

[Byron]

This is likely a GH (water hardness) issue. We will know if you can post the GH and pH.

 

[TO KYO]

This is likely a GH (water hardness) issue. We will know if you can post the GH and pH.

It was 75 but I changed my sand to play sand so I’m not sure atm. They were all eating and swimming well, but out of nowhere Started to isolate themselves and then swimming awkwardly->getting skinny->not eating->death

 

[PheonixKingZ]

Isolation can cause extreme stress...

Mollies are social creatures. Imagine if you were to just isolate yourself for a long time, you would get pretty stressed!

How exactly were you isolating them?

 

[JuiceBox52]

Isolation can cause extreme stress...

Mollies are social creatures. Imagine if you were to just isolate yourself for a long time, you would get pretty stressed!

How exactly were you isolating them?

The fish isolated themselves in the tank

 

[PheonixKingZ]

The fish isolated themselves in the tank

My point still stands that isolation = extreme stress. Do you disagree?

 

[JuiceBox52]

My point still stands that isolation = extreme stress. Do you disagree?

Nope just sayin that the OP didnt separate them

 

[Byron]

It was 75 but I changed my sand to play sand so I’m not sure atm. They were all eating and swimming well, but out of nowhere Started to isolate themselves and then swimming awkwardly->getting skinny->not eating->death

Is the 75 the GH? If yes, then presumably it is 75ppm. That is much too soft for mollies, and the shimmying in the videos is a usual first sign of GH issues. The pH is likely below 7 which is another factor. If this is the case, you won't have healthy mollies or any livebearers in this soft water.

 

[Colin_T]

My point still stands that isolation = extreme stress. Do you disagree?

yep

 

[TO KYO]

Is the 75 the GH? If yes, then presumably it is 75ppm. That is much too soft for mollies, and the shimmying in the videos is a usual first sign of GH issues. The pH is likely below 7 which is another factor. If this is the case, you won't have healthy mollies or any livebearers in this soft water.

My ph Should be 7.2-7.6 ammonia 0 nitrite 0 nitrate 0

 

[Salty&Onion]

My ph Should be 7.2-7.6 ammonia 0 nitrite 0 nitrate 0

Your tank is uncycled.

 

[TO KYO]

Is the 75 the GH? If yes, then presumably it is 75ppm. That is much too soft for mollies, and the shimmying in the videos is a usual first sign of GH issues. The pH is likely below 7 which is another factor. If this is the case, you won't have healthy mollies or any livebearers in this soft water.

My ph 7.2-7.6