Filters are passive devices as far as your automation and chlorination system.

How old are your cartridges and what makes you sure they need replacing?

Scott

The Sta-Rite System 3 cartridge filter has the lowest head loss of any filter on the market so you really can't get more efficient than that filter. However, you shouldn't need to replace them that often either. Besides Scott's questions, what model pump do you have?

If D.E is not a problem in your area for backwashing I would look at the Pentair FNS plus with a Multiport valve. This is what I have on my personnel pool with a IntelliFlo Variable Speed pump and I do a tear down clean the grids once a season and may backwash it twice a season if that much and thats because of pine trees near my pool. I have installed these filters in almost every build also over the last 6 years.

Rusty

Here is a link that might be useful: Pentair

The FNS plus with a 2" backwash valve will have about 4.5x the head loss as the OPs current filter so not very energy efficient. But then again, most sand and DE filters are not very energy efficient because of high head loss.

Well then go with the Quad DE

Here is a link that might be useful: Quad

The Quad DE is a little better but still over 3.5x the head loss of the current filter. If you leave off the backwash valve it is only 1.5x the head loss so the backwash valve adds a lot by itself.

The DE filters run a little more but being able to backwash and not have to clean the cartridges is a big plus and I have customers that are running the same grids for over 6 years. This combined would make the homeowners Pool maintenance costs off set I.M.O.