I want sand so they can still sift through the substrate and I like how debri stays on top of sand so it can be picked up by the current. I have 2 aquaclear 110 on the tank and even with a pre-filter they still catch sand and the impellers suffer. I don't want to lose those filters.
Rock and a hard place, or that`s the way it seems to me.
PFS is always brought up because it is cheap and heavy.
Not so heavy that diggers/sifters have a problem with it, but just a tail flip won`t send a bunch into suspension.
I`m right with you on being tired of material getting into filters and grinding up the components.
You would think they could make the impeller systems out of materials that can stand up to a bit of sand every now and then.
I never liked the look of a big chunk of sponge on a filter intake.
Always had a mass of poop stuck to it so that a bunch would fall off during cleaning time.
Sorry, I got no answer for you.
But me, I think the problem lies with the materials used for impeller systems and not with the type of substrata used.