What is this with my pleco

[Angelatitman]

Its yellow thing coming out

 

[JuiceBox52]

Yikes that doesn't look good! What size tank?
Did you test for ammonia,nitrite and nitrate? What were the results?
Do a 75% water change
How long has it been there?
@Colin_T may be able to help

 

[CassCats]

Plecos seem to have that strange little nub. Ive seen it on many.