Forest fire digi bleaching from bottom up

[Jake_the_reefer]

So my forest fire digitata has been bleaching from the bottom up and its bleaching faster and faster every day. It started as a little spot on the bottom and it has now covered most of the entire coral. This is the only sps in the tank that's showing any troubles. Theres nothing nearby stinging it and I have monti caps that show no problems so I doubt it's a pest.
What can I do
1.025 salinity
7.8 alk
380 calcium
78 temp
Nitrate 2
Phos .04
350 par
Moderate flow

 

[Jake_the_reefer]

Note. It's been fine for months it even started to encrust the plug

 

[Jake_the_reefer]

I might chop the good off and plant it on a plug

 

[Uncle99]

I might chop the good off and plant it on a plug

I would agree, chop, glue, you can always regrow.
I did one 6 months ago now and regrew fast.