Is this fin rot for albino Bristlenose pleco?

[JL316]

Is the white fuzzy tail fin rot or normal?  Also, is it normal for pleco to be near the surface?  They did not do this behavior the past year.  I was concerned and did a big water change today.

[Guppysnail]

Neither is normal. They hang at the surface when oxygen is low or nitrite is high. My longfins shred when I have a ph spike and they shred whenever they stress out. I would start by checking parameters and adding an airstone. They sell dissolved oxygen test kits. As the water gets warmer it holds less oxygen. 

[rockfisher]

I run a usb air pump on my tubs running a long air stone but most a large sponge filter popped in the middle when I can. Then have an air stone in the sponge filter. I would add the air regardless if the water has enough disloved Oxygen or not not. It will add a light water motion  at the surface allowing better gas exchange at the surface. 

Edited September 12, 2022 by rockfisher