Yellow growth on pleco

[Kieflow]

Hello all, I’ve noticed these yellowish spots on 2 of my 5 bristlenose plecos. 1 has a spot on its tail, 2nd is on the side of the others head. Any idea what they could be? Thanks! 

0 ammonia and nitrite, 20 nitrate, 7.5 ph, 260 ppm, 150 gh, 100 kh. 80F 

[Colu]

I can't say for sure what is affecting your bristlenose what I would do is add a small amount of aquarium salt 1 table spoon for 5 gallons and do a course of kanaplex that will cover against any possible bacterial  cause and the salt should. Help reduce the lumps