Bests & Worsts Reviews from Amazon

I have 4 toilets and I installed the fill valve in all four. I read the side of the box and apparently it was claimed that the toilet bowl is overfilled every time you flush. I did a test on my toilet to see how much water was being wasted down the drain (I am an engineer and I was curious). Before I installed the hydroclean valve, I make a mark with a pencil in the toilet bowl at the water line and disconnected the tiny rubber tube from the overflow tube (the overflow tube is that larger tube that sticks straight up in the middle of the tank near the flapper). I held the end of the tiny rubber tube so it was directed into the overflow tube like normal and flushed the toilet. The toilet bowl is refilled by the little trickle of water in that tiny tube. After the toilet tank started to refill, I waited until the water level in the toilet bowl reached the mark I made. When the water reached the mark, I redirected the the end of the little tube into a one gallon pitcher(away from the overflow tube). I was shocked when the little flow through this tube filled 3/4ths of the pitcher! This water was simply going down the drain. I couldn't believe that I was wasting three quarters of a gallon of water every single flush! When I installed the hydroclean valve, I adjusted the flow of water through the tiny tube into the overflow so that it was just enough to fill the bowl. It works like a charm. I am still waiting to see how much we save on our water bill. Also, the bottom of the toilet tanks were really cleaned by the J-tube that directed water flow to the stagnant side of the toilet tank. I thought the pictures of a dirty tank turning clean on the box were a bit overblown. The fact is that during the first flush, the sediment and scum on the bottom was stirred up and made the water very cloudy. After about 4 flushes, the bottom of the toilet tank was clean to the point that I could rub my finger on it and there was no scum, etc. (It was a little discolored due to the stain caused by the scum that sat there for years) I typically replace the flapper every year or so because the scum buildup ultimately causes water leaks. Simply put, this product is outstanding!!! It saves water and keeps the toilet tank clean preventing leaks. Every Hydroclean claim on the box was right on. I can't believe someone didn't come up with this kind of product earlier. If you want to save a LOT of water, BUY THIS VALVE!!! One quick thing though--measure the distance between the floor valve and the fill valve inlet in the back of the toilet if you don't have a flex supply tube--I had to make an extra run to the hardware store to get new flex supply tubes. Also, I replaced the flappers to start everything off new. NOVEMBER 20,2011 UPDATE: The Hydroclean valve has now been installed in my toilets for over three years now. Everything is working well. We have saved a LOT of water. One interesting thing to note--I was working on one of the toilets to replace the flapper with a new dual flush valve which prompted this update. I took a couple of pictures of the tank and one picture of the bottom of the flapper that I uploaded to Amazon. The tank was reasonably clean after 3 years, and the flapper was VERY clean. I would have thought that the flapper would have had more of that black grit on the bottom after that amount of time. See the 3 pictures I uploaded. I still highly recommend this product!