Birds nest tips browning

[Cwentz758]

So I have this birds eat that’s been in my tank since March. Usually it’s polyps are full and out. This past week I’ve noticed the tips are starting to brown and less of the polyps are extended. Nothing parameter wise has really changed except the addition on silicate to build diatoms for Dinos and I’ve been dosing Nitrate which is currently still 2-5 ppm

Alk is usually around 9.5 DKH

 

[Flippers4pups]

Brown tips may be tissue die back. Algae taking hold.