What will kill 'boatmen' in your pool if they are thriving even though your pool is correctly balanced?

Pool in balance Alkalinity between 80-120 PH 7.2-7.6 chlorine level around 3.0ppm Then from there there are 2 ways. #1 Superchlorinate That means getting your chlorine level up to 10 times where it is at Then wait for levels to go down before swimming #2This product From brody Chemical 3632095 T-SAN algaecide, 10% quat, 4 gallon only $20.00 gallon=$80.00 free shipping 800-488-2436 2-to 3 season supply