Filtration Algae scrubber doing too well?

Hey Bud,

Hope you're doing well.

Bit of a dilemma I have.

I think my scrubber is a little bit too efficient as I believe (and I could be completely wrong on this) I don't see much growth and wondering if this could be dodo with low phosphates?
It's a wild guess as I've done a ATI ICP test (see below) and apart from metals in water column (still to be located as checked everything in sump/tank and water from RO machine also checks out OK)

Tank build is a 5 x 2 x 2 with mixture of SPS/LPA and softies and only homing 4 fish and CUC so bioload is light.
Filtration is BK 180Slim and Turbo LED HF rev 4 scrubber

Dosing regime is ATO Essentials 123 @ 72ml per day per regent.

Feeding is 2 frozen cubes once lunch and sprinkle of fish food grans in evening.

As i want to increase the PO4, would a mixture of dimming down the lights and also feed more help?

As you can see below, the algae in scrubber is good and green.

I understand that there could be a number of causes for my PO4 depletion but only can see the great scrubber.

 

Hey Bud, apologies for the late response.

Well, few things happening in tank that caused a number of problems later on.

My phosphates and nitrates ran for almost near enough 0.0 and this caused a few outbreaks of cyno and dinos. Can't be 100% sure the lack of any nutrients caused it but with only running a skimmer and your great scrubber, I can only think of this.

Now for the silly issue, I started to dose phyto and sadly overdosed the amount I should on a daily basis and this caused high nitrates over some time. A 120 litre water change this weekend hopefully to see if I can get my nitrates down from 50-75 (Salifert test kit) down to a respectful 5-10. Only reason I need nitrates in tank is that since I had some, a lot of my corals are opening up and growing compared to when I hadn't any.