The retuen eyeball holes now are about 3/4" each. Enlarging the return eyeball holes sounds like a great idea! It's so simple and obvious, but completely overlooked by myself.

The only problem is that my pressure-side cleaner works best when the free return eyeball is as small as possible.

I like your suggestion so I will use larger holed eyeballs when I'm not cleaning. My sand filter will be less stressed and it will probably save a bit in electricity at the reduce load.

Thanks!