I wash sand and perlite with window screen. I lay the window screen in a large cement tub and then poor in sand or perlite. I then dump water over it and stir it around. Then I pick up the corners of the screen and make a sack out of it and lift. The water pours out and I dump the water from the tub.

Sand: I first use tap water as the sand is very salty here. Typical TDS reading is 900 the first time I pour in the water. I let it sit for a time and then pick it up like a sack and let it drain. I repeat the process a couple of times and then use RO water for a rinse or two. It takes quite a while.

Perlite: Two ways to handle this. I had some perlite that was mostly dust. I put the perlite in the screen and picked it up like a sack. I then held my breath, stood upwind, and then started shaking in. The dust poured out. Then I rinsed it in RO water. I don't use tap water as it doesn't need as much rinsing.