Is antifreeze ok for pools?

[burnszey]

does antifreeze get filtered out by the filter in the spring?

[PoolDoc]

No, it does not.

I don't know the chemical fate of antifreeze in pools, but it is NOT filterable. If you flush antifreeze into your pool, you MUST make sure to use the non-toxic propylene glycol, rather than the toxic -- kills cats and dogs -- auto antifreeze, ethylene glycol.