sand filter vs cartridge

[jkane2007]

should I continue to keep the FC high for a couple of days?

[aylad]

Yes, when fighting an algae bloom, you need to keep your chlorine at shock level for your CYA until the pool clears, the algae is gone, and you are not losing more than 1 ppm of chlorine when testing at night after the sun is off the pool and again in the morning before the sun is on the pool. After you've met all three of those conditions, then you can let your chlorine drift back down into normal ranges for your CYA.

Janet

[Poconos]

There is a trick of adding a little DE to a sand filter to get better filtration if you're looking to trap really small stuff.
Check this thread:
http://www.poolforum.com/pf2/showthr...to-sand-filter
The first post tells you the process. If you do this just keep a close eye on the pressure as it will rise quickly if you're catching stuff.
You then backwash and start again. If you really have a mess, like I have at times, I just do a quick backwash to dump most of the crud. I don't try to get the BW water totally clear until I've eliminated most of the crud. Saves water.
Al

[Watermom]

Also note that when you add the DE, the pressure may not rise instantly. Mine takes about 20-30 minutes. So don't add more if you don't see the rise immediately. If after a half hour or so you don't see a 1 psi rise, then add a little more.

[jkane2007]

Thanks I will give the DE trick a try this weekend.