Any good ways to wean a tank off Zeovit?

[Delphinus]

My 280g tank been up and running around 11 months now. It's been a zeovit tank from the get-go.

It's not really working out for me, I don't know what I'm doing wrong but the only thing the zeovit is accomplishing is draining my tank hobby funds and making it so I have less to spend on livestock.

Took a couple phosphate measurements for example, my incoming water change water measures 10ppb, the tank itself measures 30ppb, and my FOWLR (which is just live rock and a skimmer) is 40ppb. That's brutal. The zeovit is barely making a dent into the PO4 readings.

I'm worried quitting zeovit cold turkey will spike the tank. Is there any good way to ramp it down, and get a tank off this system altogether safely?