SPS bleaching, receding at base and dying tips

[toothman]

All my sod were doing great and then recently some but not all are bleaching or receding or have dying tips. Polyp extension is good to great on most. My parameters are
pH 8.2
Ca 400
Alk 8.7
Mag 1200
No3 5-10
Phos .07 with Hanna and 0 with sailfert (both new reagents)

It's mostly the red color that's bleaching and receding. Other colored sps have they dying tips.
Lighting is 5 Hydra 52 and 2 vega. For flow I have 6 vortex have mp40s.

Any help would be appreciated.

 

[whixley101]

Sounds like maybe a bad alk swing?

 

[Arron209]

Did you add any gfo lately? I added too much once and had the same symptoms.

 

[toothman]

Changed my GFO last week. Took it offline yesterday

 

[nature786]

My sps are going thru pretty much the same exact thing that u are describing.
I have been testing my alk and realized that my Alk was at 5.5 when the sps started bleaching.
I've been slowly raising the Alk and I haven't seen any other pieces suffering so hopefully this is it.

 

[toothman]

Thanks for the input