UV killing all beneficial bacteria?

[Bmezz]

Having trouble with coral growth. Po4 is very low and no3 is around 50ppm. I have a reactor with GFO and Carbon.
After reading these posts im thinking I should unplug the reactor and let P04 build?
What are thoughts here?? Need to add po4?

 

[Hans-Werner]

At least you should remove the PO4 adsorber. Use some brand of bio pellets instead to lower nitrate.