Freshwater™ Phosphate Test Strips Calcium Increaser Test the scent first by

Test the scent first by using a small amount

(1) 7/8" x 7/8" Patch

Add to spa water to prevent filter clogging and build-up and reduce maintenance

Hoyle™ Waterproof Clear Playing Cards are ultra-durable

Please Note: Not for use on fabric hot tub covers

Freshwater™ Phosphate Test Strips Calcium Increaser Test the scent first byFreshWater Phosphate Test Strips provide quick and reliable way to test your hot tub water for phosphates. High amounts of phosphates in your hot tub will create an environment that algae likes to grow in. It can be difficult to keep a residual level of free available chlorine or bromine in your spa when there are significant amounts of phosphates in the water. Test instructions are on the bottle, along with a color chart. Contains 25 test strips.