When I used to row, I got blisters at every seasonal transition. In the spring when we went back out on the water after a winter of land training, the oar shredded my hands that were no longer appropriately callused. When summer's humidity kicked in...a new set of blisters appeared. As we headed back indoors in the late fall and winter, more time on the rowing machines meant different blisters and different calluses.
People often wonder why rowers don't wear gloves. Maybe rowers do nowadays, but back when I was rowing we never wore gloves. You lose your feel for the oar. And rowing is all about feel. Rowing with a hand covered with blisters is near impossible. You have to "take care" of them. The proper technique is necessary to avoid ripping or infection. If a blister rips, it is then an open wound. It is excruciating to put any pressure on an open wound. Sitting out practice time means your boat is without you. Going without you for too long necessitates replacement. Minimizing (or avoiding) time out of the boat was of tantamount concern.
I'm sharing with you the blister-popping method that I learned back in the day. I got the blister in question on Tuesday, popped it Wednesday, ellipticalled on it Wednesday night and ran on it this morning. This method is highly effective. Watch and learn :)
Addendum: the additional peroxide use is somewhat overkill. Either peroxide or alcohol will work well.
Additional addendum: cover with a bandaid to protect it from dirt for a few days.
Remember... happy feet = happy runners :)