What in blazes is this???

[Toam]

My golden dojo loach usually is out of site, which is typical of him for the past 6 months or so. He's been out in the open the past couple of days, and fairly listless; than this evening I look and notice his skin suddenly looks like it's molting? or a form of velvet?
I'm sorry the pictures aren't any clearer, my batteries were dead and I had to lick em just to get these shots off.

big question is, what is it? and how can I treat him? I just did a water change the day before today, and he's been out the past three (I do 30% changes every saturday).
this is in a 75 gallon tank.
Also, I can tell it is definitely not ich, it's not spotty at all, more like my ADF looks when she's molting.

 

[Lotus]

Dojos will sometimes shed their slime coat if there's a huge change in parameters. Have you checked the water?

 

[Toam]

My nitrates were just starting to rise, I ahd gone almost 2 weeks with the last water change because I didn't have a chance last week. Now that you mention them shedding their coat, that could explain a lot. I also did a 2 degree drop when i did the water. My nitrates are back around 5-10 they were up to almost 30 though. Is that too much? ammon and nitrite were nil.
I also did just add another 80 watts to my tank? went from 80 watts to 160 watts.

edit: i entered my paramters wrong the first time. edited them to the right levels.

 

[PlecoCollector]

NitrAtes are fine up 40ppm. After that, they start getting high. As long as your NitrItes and Ammonia are at 0, you shouldn't have to worry much about your NitrAtes. Just make sure they don't spike too far above 40.