These Leak Detection tablets will detect toilet leaks in minutes. Simply drop 1 into your toilet tank and wait a few minutes. Do not flush the toilet. If the toilet water turns blue, the seal around the flapper is leaking water from the tank to the bowl. This type of leak is often very hard to detect because it may not make filling or leaking noises or the fill valve may only kick on every 10 or 20 minutes (while you’re not present). If your flapper is leaking, replace the flapper or toilet immediately. This is the most common water wasting problem in the home – it can rack up your water bill fast and you may not find out until you get your bill! If your toilet has a leak you could be wasting 200 gallons of water a day.