Depends on where you are, and the pool temp, and how much crud gets into your pool, and if it rains alot.

Generally, from the time the sun is really out (mid morning) to just before the sun is down (late late afternoon). Same for winter (since the water is colder, and the pool does not get used as much, the need for filtering isn't as great, so the hours can be reduced.)

A few hours is not enough.

Sand filters rule, but are big and bulky, and have that gasket that you have to get in there just so, or the darn thing leaks. Cartridge filters cost you more in the long run because...well, because you keep having to replace the cartridge once the bands around the pleats break.

I've never had a Diatomaceous earth filter myself. All I know is the "sand" they use is super super fine and reminds me of gray clay.

Good luck with your pool. Get a test kit, and keep an eye on your chlorine and your ph level. Check your total alkalinity about once every 3 months.

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D