I opened late this season (3 days ago), and had a large algae bloom, so doing a SLAM....water levels for the SLAM are good and maintaining good FC. Doing my usual opening routine....SLAM, lots of brushing, back washing when filter pressure ramps up....but for some reason it's taking longer than usual to get algae filtered out this year....Sand filter is 3 years old so sand should be ok but behavior not quite what I remember from past openings.
-Running pump 24 hrs since opening
-Normal pressure when filter is clean is about 12 at 3300 rpm.
-First day filter pressure acted normally, had a rise to about 16 within a few hours...backwashed....rise again another 6-8 hours later...normal opening stuff.
-But since then while the water has gotten clearer in terms of sediment etc, it's still very green (improved since opening but a long way to go) and I don't remember it taking more than 2 days in past seasons.
-After the first day the pressure hasn't risen very much even though lots of dead algae (FC levels staying above SLAM levels), so I charged the filter w/ some DE. Done this in the past and 2 cups usually works well.
-Pressure ok first 30 min...but about 2 hours later...pressure spiked to 25.....backwashed.....eased up how much DE.....went to 1/2 a cup....lasted maybe 4 hours before pressure spiked to 25 again....tried one more time w/ 1/2 cup....same thing. So obviously still lots of algae the DE starts catching......but still fairly green.
-So after last backwash today I didn't want anymore spikes so no more added DE today....but now the pressure has barely risen after 12 hours (from 12 to maybe 13-14)...still lots of dead algae in the pool to filter and still green but for some reason the sand isn't handling it this year.
Does it sound like there isn't enough sand, or that the sand needs replacing? Anything I can do to improve the filtering outside the DE (can't stay on top of those pressure spikes every 2-4 hours this weekend)?
Thanks
-Running pump 24 hrs since opening
-Normal pressure when filter is clean is about 12 at 3300 rpm.
-First day filter pressure acted normally, had a rise to about 16 within a few hours...backwashed....rise again another 6-8 hours later...normal opening stuff.
-But since then while the water has gotten clearer in terms of sediment etc, it's still very green (improved since opening but a long way to go) and I don't remember it taking more than 2 days in past seasons.
-After the first day the pressure hasn't risen very much even though lots of dead algae (FC levels staying above SLAM levels), so I charged the filter w/ some DE. Done this in the past and 2 cups usually works well.
-Pressure ok first 30 min...but about 2 hours later...pressure spiked to 25.....backwashed.....eased up how much DE.....went to 1/2 a cup....lasted maybe 4 hours before pressure spiked to 25 again....tried one more time w/ 1/2 cup....same thing. So obviously still lots of algae the DE starts catching......but still fairly green.
-So after last backwash today I didn't want anymore spikes so no more added DE today....but now the pressure has barely risen after 12 hours (from 12 to maybe 13-14)...still lots of dead algae in the pool to filter and still green but for some reason the sand isn't handling it this year.
Does it sound like there isn't enough sand, or that the sand needs replacing? Anything I can do to improve the filtering outside the DE (can't stay on top of those pressure spikes every 2-4 hours this weekend)?
Thanks
