Which multi-port setting when vacuuming pool?

[Elle W]

New to pool maintenance, teaching myself with the internet and youtube. Some say vacuum on filter mode, others say vacuum on waste mode. Which is correct and why?

[Teapot]

Depends on how much crap there is. You don't want to fill your filter with a whole load of crud. Then you'll waste more water back washing the filter clean and some fine stuff will pass through and back into the pool. Ok for small amounts.
Really dirty pools full of crud should be vacuumed to waste but that also uses a fair bit of water.

Best plan don't get the dirt in the pool.

[Elle W]

Best plan don't get the dirt in the pool.

Yes, but that's hard when living in the windy dusty desert . Thanks for your help. The pressure is already high - should I backwash and add DE first, then vacuum on waste (and then maybe backwash again), or is it ok to vacuum on waste first? Pool is really dirty right now because we had a big dust storm.

[Teapot]

A good cover stops the dirt getting in.
Being a DE filter vac to waste, you'll clog the filter in no time and spend a fortune on DE powder and get covered in it to. The high pressure (please state) won't effect vac to waste then you can have nice clean DE when you backwash afterwards.
When you get bored of DE change to a sand filter the Dr Drydens "activate" glass media.

[Elle W]

Thank you. The pressure is at 31, it's supposed to be 30 or less. So if I understand what you're saying correctly, I vacuum first, on waste mode, then give it a good backwash and add DE. Is that right? Sorry if I seem slow to catch on, I'm really new to all this. Thanks.