I let it sit on the filter for a long time (3 weeks) before backwash. I'd think that it should have finished.

A couple observations:
It took about three days to clear the cloud with each addition of phosphate remover. That's with the 27" sand filter and moving 40gpm in the sun and 10 gpm all the rest of the time. The cloud was minor, more of a dulling of the pool than a cloud. At night, I could see the beam of a bright, focused flashlight in the water.

When I added the first and second half-quart doses, the pool water smelled strongly like laundry.

After every dose the surface tension appeared to change dramatically - the water looked thick and the roil on the surface near the return was far more pronounced.

I hope to provide better info in August - the beginning of the summer has been crazy for us.

@PoolDoc: I realize this is now prety for off-topic from the original thread. Sorry. It might be a good idea to move it to the previous PO4 remover thread or make a new one to collect observations.