Not sure if this photo has uploaded, but we purchased a home with a pool last September. It is about 21000 gallon gunnite / plaster pool with 0.75hp (1.5 SF) superpump and sand filter. The tag on the sand filter indicates "Super Clear" and lists specs on 3 models (S400, S-500, and S-600, with a small blue water drop in the S400 box). The filter is about 24" in diameter and has a 1.5 in Haywood multiport on top.
The question I have: is this filter really a S400 (which indicates 100 lbs of sand, 35 gpm flow rate. Doesn't seem like a lot of filter media for a pool this size.
The S-500 and S-600 show 175# and 225# respectively as well as 40 gpm and 50 gpm flow rates. I was thinking this was a legacy Hayward filter, but not sure.
Planning on upgrading pump before June to a 2-speed or variable speed (the latter may be worth the slight upcharge for flexibility, understanding that in my area, the economics are not perfect).
Thoughts are appreciated.