I started out with a RayMarine system on my 22, and I believe a .5 pump. Didn't work worth crap. I ended up going with the Reactor 40 and the smart pump. Worked great, and continued to work well when I transferred it to my 25. I suspect the 1.2 pump would work. But you won't be dissatisfied with the smart pump. I guess it's like motors. Some guys like the extra horsepower, even if they don't need it. In this case, you pay more up front, but it's not costing you anymore down line. And if you ever need more capacity, you already have it. The nice thing about the smartpump, is it provides variable pressure to what's needed. Colby