30C is more of a max and not somethign you want long-term. They'll survive and produce within reason, if not well, at 30C. 20C-30C is generally what they recommend as a min.max. 77F or 23C (going by memory, but think these 2 sync up like 30/86) i think is good for regular CO2 ppms, but you want higher temps if you pump in CO2? That type of detail requires google to verify.