Please help ID

[Lucius]

So the other night my sailfin started to get irritation on its skin. It got better but now is spreading. Please help me iD this...

 

[beth]

It looks like a massive infection. How long did it take for this to develop? What are your water readings? How long have you had this fish? Size tank?

 

[Lucius]

I've had it for over 2 years now and never had any problems with it. I know my nitrates are slightly high but have been for awhile and I've been working on getting them down. I added a mandarin a few weeks back but it came up Friday night and cleared up nicely sat so I thought maybe he just got into a tangle with a anemone... Today it's kinda bubbly looking tho like he's been itching it.. I'm going to try to get a good updated pic

 

[Lucius]

And it's a 75 gallon right now with a 30 gallon sump. I

 

[beth]

These are not good pics really to be definitive. What are your nitrates? I'm assuming you don't have a hospital tank?