You might want to look into using a variable speed
pump that operates with a pressure sensor to control
pump output based on how much water is being demanded (Jabsco and Shurflo make them). They're a bit more expensive (about $75-100 more) but they eliminate the need for the accumulator tank. You do have to be careful of water consumption, however, as they can operate at fairly high pressures. I installed one several years ago when I got a water filter/purifier (Sea Gull IV) that required more pressure than the old PAR (with an accumulator tank) would put out. I've had both Shurflo and Jabsco
pumps on the boat -- the Shurflo Smart Sensor was replaced twice (on warranty) and I now have a Jabsco that works well. One disadvantage (aside from price) is that they are fairly quiet -- if you spring a leak somewhere, as we did once, you can end up with a bilge full of fresh water pretty quickly. Shurflo has a modification you can install that will light an LED when the
pump is operating.