Albino bristlenose pleco turning red

[maggie.bf]

Hi All,
My husbands albino bristlenose pleco started turning red, from his 'nose' onto his 'tummy'. It's a still rather new tank (started 30th Dec 2020). My husband brought the pleco (Geoffrey) two weeks ago. All was fine until yesterday. My son has a mature tank and his pleco is absolutely fine. I tired to attach few photos. It looks like Geoffrey scraped his 'tummy'.
I would be grateful for any advice.

 

[libertybelle]

Red streaks can also be due to ammonia poisoning. Have you tested the water (ammonia/nitrite/nitrate). If so we need those numbers. If not, given that this is a newer tank, do a 50% water change and get a test kit ASAP.