I've used fine beach sand for over a decade. And builders sand which
needs to be rinsed well.

You always end up siphoning some out when you chnage water. Maybe a tablespoon
or so per 5 gal bucket. Every few years I add maybe a handful of new sand.

It's not a big deal.

The nice thing is nothing can get stuck in gaps like what happens
with courser grained gravels.

--
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