Your PO4 is ok. As long as it is not zero or above 0.09
You just need to lower your NO3.
Water change has little effect of bringing down NO3 unless we are talking about major water change.
Skimmer is more effective in bringing down your NO3 . So try to run it wet.
You running biopellet reactor . What media you running?
You have bacteria king and marine pure. Are you dosing bacteria?