How often should sand in a sand filter be replaced?

Just bought new home has 28' cirlce above ground pool. Opened 2 days ago. Filled and started pump. Seems like the filter is not keeping up. Don't have any info from previous owner. All chem levels are right on. Help.

Hi,and welcome to the forum!

I'm not sure what the exact question is, and what you mean by "the filter is not keeping up". If you could please post test results from a drop-based test for your chem levels, as well as the appearance of your pool water (blue, green, cloudy, murky, etc) I'm sure we can give you a hand!

Janet

Generally, the answer is "No", sand is good pretty much indefinitely.

PH is 6.8 chl is 2.5 kinda green in color have put in algecide and clarifier.

+ Forget about the algaecide and clarifier
+ Add 2 gallons of BLEACH per 10,000 gallons in the PM.
+ Add one box of 20 Mule Team borax, per 10,000 gallons per day, till your pH is above 7.2
+ Test daily BEFORE adding bleach with a cheap OTO / phenol red test kit.
+ Report results here.

+ Continue to add bleach daily unless pre-bleach evening test shows "orange" OTO levels
+ Use strips or have pool store test your water to determine stabilizer levels.

+ Do NOT add goop: clarifiers, enzymes, phosphate removers, etc.
+ Do NOT 'balance' (increase alkalinity or calcium or adjust pH) except as per borax above.
+ Do NOT let chlorine get low, ESPECIALLY while your pool is green.

+ Once your pool is bluish, TEST your filter by adding a small amount of DE powder (pool store, maybe). If the DE returns into the pool (as a cloud from the pool returns, your filter needs work. If not, it is functioning more or less.

**** NOTE: Mods, others, this is using DE for TESTING, not for filter enhancement. The point here is to see if the filter *****
************************** is working, not to improve algae removal. ****************************************

Ben