After reading as much information as possible, l still cannot decide which filter (sand or cartridge) to buy. Hopefully I can get some help in next few days from any one of you, so I can replace them in next couple weeks as I think the filter may go out soon.
Here is the situation, I have few trees around my pool, including bamboo & pine trees, and they drop leaves constantly, including bark once a year, plus a sandy backyard(trying to establish it, but not enough money to do it at the moment when we need to replace the pool equipment), so we constantly have to vacuum, hence backwash(we have a sand filter at the moment). I don't mind cleaning, but would prefer to reduce the time of maintaining and balancing chemical.
I know the pros and cons of these 2 type of filter(sand & cartridge), and I know it doesn't matter which one i go for as long as l feel confident my choice will reduce my maintenance time. What I don't know is under the circumstances (A)which one is the most suitable in terms of money , efficiency, and less labour intensive ? (B) the size of the filter listed below, are they correct ? (C)If go for cartridge, how often do l have to replace the filter because of the debris, leaves, sand l get(manual said replace every 3 years!?) (D) Bigger is better for filter, but if l go one size smaller(i.e. 325sq ft filtration area) would that still be all right?
Astral C320: 50mm pipe, 0.3 sq m filtration area
Hayward Pro S270: 50mm pipe, 0.34 sq m filtration area(I know S310 is more ideal, not enough room for clearance)
Onga Pentair II P229: 50mm pipe, 0.397 sq m filtration area
Astral Viron CL400: 38 sq m(400 sq ft) filtration area
Hayward Swimclear C4025: 39.5 sq m(425sq ft)
The pump will be Hayward MaxFlow SP2300VS. Pool: 60,000 Litre, ~15,850 gallon
Any help appreciated