it wont kill them at all
however, the algae wont mind it happening too much either. the best way to kill it is to lower you nutrient levels by doing such things as more frehwnt water changes, skimming more, feedingless, and making sure you are using good water.
This "red algae" is the slimey cyano bacteria, right? If so, what's your water flow like? I ask becuase getting rid of cyano can be as easy as adding a few powerheads.
And, the "brown" algae is diatoms, right? If so that's very common in new setups and will go awya after a few months of the tank being up.