Check the listing for details. SEACHEM PH ALERT WATER TEST FRESHWATER FREE SHIPPING. Condition: New. Listed at 12.25 USD. SEACHEM PH ALERT Listing is for ( 1 ) : SEACHEM PH ALERT Seachem sensor technology Continuously monitors pH in freshwater No tests, no strips Lasts up to 4 times as long as competing products Description : 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 to alert you shifts to in pH levels between 5.4 and 8.0. No tests, no strips, just constant readings. Freshwater Only pH Alert® lasts up to 4 times as long as competing products. pH Alert® is also almost half the size of competing products (1.5" x 2.5"). It's small, clear, and unobtrusive, so it won't detract from the view of your aquarium. Directions: Simply place pH Alert® visibly anywhere in the aquarium or filter. 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. Care: No care is required beyond removing algae with a clean, soft material. Avoid touching the sensor with fingers, since skin oils can damage it. Do not use bleach, soap, detergents or hard objects to clean the sensor. Some dye medications may discolor the sensor. For maximum sensitivity, the unit should be read under natural daylight or daylight simulating light. Please feel free to contact me for International and combined auction shipping rates or with any questions or concerns that you may have about my product. Thank you !