UnderWaterVanya said:While we are on the subject of changes - where do I find the filter sizing chart? I have seen one here somewhere.
I have a filter that is considered undersized (S210T) but I can't recall how much undersized it is. I have no plans to change it as it is working well for me. However I did pick up a cheap Waterway Pro-Clean 175 square foot cartridge filter (unused) for $20 on Craigslist as a spare filter in case anything should go wrong with this system. There is no cartridge included (about $85 online). I think I read this too is undersized by TFP recommendations but is it as close as what I have? For $20 I felt hard pressed to not pick it up.
The table is in the middle of the second post here:
hydraulics-101-have-you-lost-your-head-t915.html
I think the "general" recommendation is double the size in the table for cartridge and DE, but the same as the table for sand. Although every pool is different and some of the sizing depends on the pump as well (for backwashing Sand etc). But, I think the bigger the better as far as cartridges are concerned.
For your pool size, from the table: ~200sqft cartridge, ~35sqft DE, ~2.5sqft sand.