GHA taking over tank with low phosphate levels

[Reef_dachs]

Hey all,

I’ve got a reefing buddy with a 5 year old 25 gal AIO mixed reef. The tank is overrun with GHA . I feel like I’ve thought of everything to test or ask in regards to lights and food. What am I missing?

Parameters:
Phosphate - .04
Mag 1280
Cal 430
Alk 8.4
Nitrate 4.2
Nitrite 0
Ammonia 0

(1) Kessil blue mounted 14” above the tank, running blues & minimal white for 2 hours

Food - frozen brine & rotifers
No dosing or amino acids

Weekly 10% water changes

 

[Lavey29]

Raise magnesium to 1500. Lots of manual removal and weekly water changes. Diverse cleaner crew with urchins and turbos. No white light for several weeks just blue and UV.