Sick Anthias in QT, missing scales/lesions

[pfoxgrover]

I have 9 Ignitus Anthias in a 75g QT. I just noticed missing scales/lesions on two of them.The areas are on their backs and base of the tail. Here is a few photos.

I have not noticed if these to fish are getting picked on in particular. Does this look like a disease or damage from the other Anthias?
They are the only fish in this QT tank.

 

[pfoxgrover]

the worst of the two is dead already

I noticed he wasn't eating and was getting picked on a little so I separated from the other fish but she died a few hours later.

The other one still seems to be swimming and eating. I assume this is damage from the other Anthias but I wish I knew.

I hope this isn't something that will take down the whole group. I started with 10 and now I'm down to 8. Two of which I have never seen eat.

Does this look familiar to anyone?

 

[pfoxgrover]

2 time looser

2 time looser

Well I finished quarantine on that batch of Anthias. I ended up loosing half of the 10. The other 5 are doing well.

I started QT on a second batch of 5 more. These ones were smaller.
I am about at the same point in the process and now I had 2 die and the last three have the same red blotch on there side just in front of the tail.

I lost one of the three yesterday.

I have not seen any fighting in the tank.

Can someone tell me what is causing these?

Any ideas would be appreciated!

 

[2JZGTE]

Ammonia poisoning?

 

[Mrscribbled]

Have they been treated for flukes and internal parasites? Anthias usually come with these.

 

[pfoxgrover]

Ammonia is zero.
I treated with prazipro once a week ago.
I noticed the salinity had creeped up to like 39 ppt. I lowed it to 35 ppt over a few hours.

I wasn't watching the evaporation close enough. They are in 29 g tank that was never full to the top so the change in water level didn't seem that much.

Does the high salinity seem like it contributed to the weird red areas?