Help ID illness - black molly

She almost looks pineconed, but only one one portion of one side of her body. I'm not sure what causes this and how to treat? I have her isolated in the hospital tank. I've got aquarium salt in there (2 tablespoons - 10 gallons of water), but have not treated with anything else. I added the aquarium salt mostly because I had already put the same amount in the big tank and did not want to shock her when moving her from the other tank, so I figured the same amount of salt would be a good idea.

What to do next though?

Pics attached - the first is of her left side, which appears to be perfectly fine. The rest are of her right side, which are definitely not fine, but I am not sure what it is, or what to do about it.

Help?

Ph has remained steady around 7.8 (yes, I know high but it has always been high, and these guys were drip acclimated, so no big shocks)

Ammonia 0
Nitrite 0
Nitrate 0 (new water - used dechlor), and it's got a cycled filter on it (I keep it cycled by running it on my 46 gal tank when it is not needed for the hospital tank). It's an Aqauclear HOB, meant to filter tanks up to 20 gal I believe.

Nothing in the tank but this fish and a string of hornwort that came along on the net from the 75 gal that she was in.

I have no meds on hand, so need to know what to purchase.

So far I have not noticed it getting larger. I just noticed the spot last night, and as of today it was not any better, so I moved her to the hospital tank once I set that up after work.

No behavior symptoms. Just the patch. It came on all at once from what I could see.

The only other stock in the tank are the mollies she was added to the tank with last week. They all appear to be healthy. These are new fish in my 75 gal setup. The tank is cycled (fishless cycle), and they are the first additions.

The plants, etc were all there prior to the fish being added. I have tested the water daily since adding the fish - no spikes in any of the parameters, and nitrates have stayed below 10. She has not given birth since I picked her up. I believe she is prego and probably due in 2-3 weeks. I have no idea how old she is.

The hospital tank was set up today, water was added, dechlor added, filter added, heater added, salt added and then fish added, in that order. I waited until the temp of the hospital tank was the same as that of the main tank that she came from, and then added her so that there were no shock factors.

water is perfect at this point. I will add more salt and see how she does.

I am not sure what the water params were like prior to me bringing her home. She was in a tiny (maybe 30 gal) tank with a lot of fish (15-20 mollies and probably 10 diamond tetras) and one filter. I don't know if the filtration was decent or not - it was an HOB in an octagon tank.

Anyhow, the rest as I said seem to be healthy. I did have one other die of complications from dropping fry - she literally died as soon as she stopped dropping the fry, and she looked perfectly healthy pre-birth, so I am fairly certain that the death was a birth related one.

There has been zero ammonia since bringing them home, so I can't think that ammonia would be the issue, although if she were exposed to it prior to me taking her home, that could be a problem. I did drip acclimate, as I mentioned, just to be on the safe side, and all seemed well up until yesterday.

I'll keep an eye on her and add another two tablespoons of salt and see how things look.

Any other suggestions welcome.

Thanks.

Reading the descriptions on both of those do not make them sound like this disease. They're both symptomized by lethargy, clamped fins, cloudiness, etc. None of that is relevant with her at this point. I guess I will continue to watch and see how she does with the increased aquarium salt.

As of this morning she is still behaving normally, it still looks exactly the same. She begged for breakfast (and ate it quickly), so I am hoping she pulls through. I will check water parameters after work and will do a W/C if there is any sign of nitrates (or anything else).

Not sure on the water hardness. been so long since I've tested it specifically since I never had any issues with it. I'll check that when I get home today. And I already have aquarium salt at home, so may as well use it. Plus I've read that table salt is not the same thing, and don't want to introduce further problems... unless I'm just thinking of marine salt vs table salt, which I know is very different. Perhaps aquarium salt is more of a similar makeup to table salt and I've got my salts mixed up. I'll have to do some re-reading.

I talked to the LFS about it and they are supposed to be calling me back if they can come up with any further suggestions, plus they are checking their stock for any issues.

This morning she was fine, other than the spot, so I'm hoping she'll recover. She does not seem uncomfortable or otherwise symptomatic, but I know that can easily change. I have my fingers crossed that she will pull through. She's a beautiful molly, and I'd hate to lose her.