There is such a thing as too high of pH, yes BUT it wont happen naturally in our tanks. By that I mean you would have to put in some work to get to a point where you see adverse affects. I rock the same range as you do; low of around 8.2 high closer to 8.5. Keep up the good work.
EDIT: saw you mentioned you were running a C02 scrubber, with those numbers I'd say its not necessary, at least maybe until winter when its a gazillion degrees below zero and the house has been closed up for weeks. If you are buying your soda lime from a medical/vet supply and its cheap then rock on, but if you are getting it from BRS or elsewhere, where they charge a hefty premium, I'd only run it when you cant get above 8.2.