I recently moved to a house that has a recreational pool (volleyball sized) - about 14,000 gallons. The DE filter system is probably as old as the pool (25 years) so I'm inclined to replace it. Looking for any recommendations, do's, don'ts, etc? Pool has a 2HP Pentair pump, spa has a supplemental pump (also 2HP). Supplemental pump does not run except when additional jets in spa are desired. I don't mind learning and I understand buying a new DE filter may also require a new backwash filter. I just want a good, long-lasting, effective, fairly low maintenance system. Thank you! SLB