Had a tetra and a pleco that lived together for over 12 years. So 2.5 is nothing for that little guy.
Good luck! Mine was a hardy lil devil. We inherrited (sp?) the tank, I don't think the water had been changed in years. I cleaned it up, added fish, and that Tetra would not accept any "newcomers" into the tank. So back down to just the Tetra & the pleco. I cried the day the pleco died- he was huge considering the environment he had been in, his name was Grandpa!