Fill Valve. The Hydro Clean 660 by MJSI has a couple of features not found on most toilet fill valves. First, it can be adjusted to make the tank and the bowl hit their fill levels simultaneously, preventing water waste caused by the bowl filling faster. Water savings can be as high as 30 percent, the maker says. Second, the valve has water jets that remove sediment and slime from the bottom of the tank with each flush. It’s available online for about $15. MJSI, 888/466-5741, gomjsi.com.