Our puffer usually has a smooth texture & his base color is usually perfect. No dark spots besides the obvious black markings! I noticed the difference (right off the bat) when I woke up yesterday. The hubby asked about him as soon as he looked at him too (I hadn't said anything yet). The bumps were way more visible before I took pictures. They seem to had gone down after we fed him...I wasn't too worried, since he was eating normal. He has some weird markings/scars now, where the bumpy bumps were. My hubby instantly thought "rash" & "liver spots" when he saw it.
Nitrates went down today, salt level was 15 according to LFS when we did our routine visit. Though our floating hydrometer was 19...I know the floats are known to be inaccurate at times tho...only added half the amount of salt than what the LFS guy told us (had never seen him before, so was a little iffy!). Out of town until tomorrow night, hopefully all is well.
And yes, it's just a fish only tank. I am aware that the nitrates are different for such a tank. But, it was keeping a steady number until recently...which I don't know the numbers, because I make the hubby do it.
Yes, we give him a variety of foods. Before we adopted him (may 09), he fed on small pellets all his life...so he's enjoying himself now!
One last thing, he poofed out for no reason before we left town today. Do puffers puff out even when they're not being threatened by another fish? He did it far away from everyone else...