Is this ick?

[29Gsaltaquatics]

I am pretty sure it is not ick. I treated it for days - weeks and none of my other fish have it. It is too big to be ick and it happen within 5 minutes. Is it fungus? Parasite? Bacteria? The pleco is very healthy and active. In fact it is the first time I have ever seen him eat!
He is a Clown Pleco. The large-ish spots are on his tail area. They are not even circles they are like ovals and other shapes. I did a saltwater dip (safely for the pleco) to get ick off him from a week ago, and I heard that they lose their %25 of there slim coat. Could that be it?

Parameters:

Ammonia: 0
Nitrite: 0
Nitrate: 7.5
pH: 7.2
Phosphates: 5 (working on getting them very low)(BTW high phosphates doesn't affect fish)
dKH: 3
dGH: 4
Temperature: 78

Thank you!

 

[V227]

It's been my experience that Plecos are very ick resistant. I've kept many different varieties of Pleco over the years and never had one get sick with anything.
Sounds like you thoroughly treated the fish and noted that he appears healthy other than a few symmetrical spots.
Watch to see if the Pleco begins to glance off rocks or swim erratically, but as long as he is eating and the spots don't spread or worsen, I wouldn't worry too much.
Good luck.

 

[Z3N157]

I had ick on the used tank I bought during cycling and it was on my common pleco. It didn't look like that so much and had more than one, we caught it when they were very small though. Raised water temp for two weeks, slowly, and it was all good. If I have a pic still i will link so you can compare but I don't believe I do.