Color of pleco when it died

Question
I had asked Amber W. if she knew how/why my blackish dk brown wide and ugly Pleco died. Had him for 3 months. Change water every week 20% and tank is crystal clear. All other fish are happy and fine. He was fine a few days ago and yesterday I found him lying on his back and a light gray.(Amber had asked what color he was when I found him)she said she would be able to tell what he died from. I cannot reach her with my answer. I do keep my tank around 79 degrees.
Thank you for any of your input.
Mrs  Isabel Martin
isabelroberts10@hotmail.com

Answer
Hi Isabel,
  This is an interesting question.  I have noticed a similar problem with other plecostomus, i.e., they do fine for a little while and then die for no apparent reason.  I suspect it has to do with diet.  Plecos eat wood and algae and this takes a rather impressive gut fauna to break that down (much like a horse or cow) since it isn't very nutritious and is hard to digest. I think what happens is that sometimes when a pleco is moved, it is unable to adjust to the slighlty new diet.  I have witnessed this several times with my own plecos.    

-- Ron
  rcoleman@cichlidresearch.com
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