need advice on changing out my zeobrite to regular sand

20k, I/G vinyl liner pool. moderate algae on start up mid to late may. Ive shocked and added algaecide to where its now a hazy blue.I can see heavy particulate in the water at night using a bright light. I currently have a Hayward sand filter with 100lbs of zeobrite that's about 4 yrs old now.
I don't feel my filter is doing its job and want some advice on weather to change out to straight sand. Ive done all the backwashing needed and do add de after backwash cycles.

filter runs 12-14 hrs a day and more often the first week of opening. currently I cannot see the deep end bottom.

opinions of zeo are mixed , but seem more to its not needed.

How long should a sand filter take to filter out floating particulate in the water?

ive never done any filter cleaning internally other than a backwash. Its a decent amount of time to separate the top and bottom filter lids to access the sand to chemically clean or hose clean as ive read.

I feel I run the filter a good amount of time and keep the chemical levels good. Im trying to be steered on the correct path before I attempt various things.
ive heard some instances where the sand becomes channeled or muddy inside the filter. My pressure are ok though and I have good flow.
thank you for reading.