sand box sand or pool filter sand?

Pool filter sand is larger grained, and more uniform. It is WAY easier to rinse...I generally just rinse it in the tank, do a water change, repeat then done...

It also doesn't compact like play sand. Easier for snails etc to burrow in and easier to plant in.

I suspect both come from the same source but out of a different sieve.

If you dont like the look of Pool Filter sand, mix in 1/3 well-rinsed play sand. Works well.

Sand box sand (play sand) is dirtier, dustier, much harder to rinse so as to produce cloud-free water, is not as heavy or uniform - gets picked up easily with vacuuming, tends to clog filter impellers - the list goes on.
PFS is clean - almost rinse-free - a better color - doesn't compact - about the same price as play sand.
PFS is generally white silica specifically geared for (pool) filtration effectiveness - need we say more ?
There's really no comparison - get PFS !

The Kwikcrete play sand I'm using rinses clear after three buckets of water. Got it at Lowes for $2.14 per bag. I blend sand and gravel so there are areas of each. To me that looks more natural than pure sand or pure gravel.