Softswim "B" - 1/2 Gal BioGuard Softswim B - 1/2 Gallon Sanitizer for the Softswim Program containing Biguanide and is step 2 in the Softswim Program Kills and controls harmful bacteria and is gentle on eyes, hair and skin Softswim B is UV-Shielded and is resistant to evaporating in the sun 1 Pt. per 10,000 gallons of water to raise level by 10ppm