90-Day Algicide Returning An Empty Bottle?:Yes A clear comparator block and

A clear comparator block and color-coded instructions make it simple to use

and blue-green algae

75 oz DPD reagents and full color-coded instructions

vinyl liner

Quickly clears floating debris from pool and spa surfaces

90-Day Algicide Returning An Empty Bottle?:Yes A clear comparator block andLong lasting protection. Just one dose every 3 months This 90 Day Algicide is a powerful, copper based formula designed to kill and prevent all common types of pool algae including black, blue green, and mustard varieties. One treatment lasts up to 90 days, keeping your water clear and protected all season long. The non staining, slow release formula is safe for all pool finishes and works alongside chlorine, bromine, and saltwater systems. It