Testing the bromine, pH, total Alkalinity and water hardness levels in your hot tub water or swimming pool is easier then ever with the AquaChek Red 4-in1 test strips. The AquaChek Red 4-in-1 test strips provide accurate results with a simple testing procedure. No need to measure drops or have bottles of reagents for testing, simply dip a test strip in the pool or hot tub water, pull it out immediately and compare against the colors on the back of the bottle, yes its that simple.