High nutrition cause Acros pale color?

[James-reefer2017]

I got 2 Acros losing their colors, one from green, one from yellow, both are pale now.
KH-8.5
Cal-430
Mg-1300
PO4- 0.75
NO3- 50-100
I know PO4 and NO3 reading are bit ridiculous, but that’s the way how my tank all SPS got survived from very low. so I decide to let it be. I don’t see any GHA problem. All Corals are ok except these 2 Acros losing colors, becoming pale, not bleach), I thought that only low nutrition causing that. That seems it’s not this case in my tank. Any advise?

 

[Hincapiej4]

It could be flow. Your flow would provide them those nutrients. Maybe you need a bit more ? It depends, you know better than I if you need more. Is your ALK/PH stable...(actually, naw that would just cause stn/rtn....)

...Yea, I'm going with flow.

 

[mdb_talon]

High nitrates/phosphates can cause acros to lose color. That would be my best guess with those numbers.

 

[James-reefer2017]

It could be flow. Your flow would provide them those nutrients. Maybe you need a bit more ? It depends, you know better than I if you need more. Is your ALK/PH stable...(actually, naw that would just cause stn/rtn....)

...Yea, I'm going with flow.

Alk/ph are stable , you mean flow too strong or weak? The thing is that they were good for long time, it happened recent week. They r always in the same spot

 

[James-reefer2017]

High nitrates/phosphates can cause acros to lose color. That would be my best guess with those numbers.

That’s my concern too, I think I’m trying to reduce them little by little to see how it goes

 

[X-37B]

Alk/ph are stable , you mean flow too strong or weak? The thing is that they were good for long time, it happened recent week. They r always in the same spot

Yes but how long have your numbers beem this high?

 

[James-reefer2017]

Yes but how long have your numbers beem this high?

It’s been long time at lease half year ,since all corals are fine , so I didn’t try to reduce them, especially I don’t see any green algae problems . At 2019, the best growing and coloring for my SPS is the tank with green algae problems.

 

[ScottB]

Do you have other acropora that are doing fine?
Can you load a few pictures of the tank and the coral. Under white lights if you can.

 

[James-reefer2017]

Do you have other acropora that are doing fine?
Can you load a few pictures of the tank and the coral. Under white lights if you can.

Other Acros are fine, I can’t say they r very happy if comparing when they stayed in my my previous tank

 

[James-reefer2017]

The first photo are the ones losing color

 

[James-reefer2017]

I have changed GFO media , Po4 dropped to 0.58 yesterday , hope this swing r ok for them