Seachem Laboratories pH Alert 6 Month Monitor

pH Alert® is a unique color device designed to be placed in the aquarium or filter and monitor pH continuously. A sensor changes color reversibly from yellow to orange to red alerting you to shifts in pH levels between 5.4 and 8.0. Freshwater use only.
pH Balance: 5.4 - 8.0 pH pH

Use Instructions: Simply place pH Alert visibly anywhere in the aquarium or filter and match the sensor color to the corresponding pH reading on the color wheel. It’s that easy. No chemicals or test procedures are required. When first put in service, response time will be about 30 minutes. Thereafter, pH shifts will register within ten minutes."
Product Gross Weight: 0.0200 lb, Product Net Weight: 0.0200 lb, Product Height: 0.75 in, Product Length: 6.00 in, Product Width: 4.00 in