My 12 day trip and montipora

I have a 46 gallon and was always adding kalk to my top off rodi water that I would add some in the morning and night along with reefcode A and B in morning and night. I went away for 12 days and my friend added water every other day that I added part A to 1/3 gallon and part B to the other 1/3 gallon of water. My temp used to be 78 but it dropped to 74 when I came home. My monti seems to have died. Is this from the lack of the kalk or the temp. I tested the water and the alk was 6 but cal said 440. 1.024 sg, and ph was 8. I usually keep the sg at 1.026 and temp at 77.
Picures 001 and 002 are now! 022 was 3 weeks ago when I had no problem. There was no kalk added to the water during the 12 days I was away. Will the monti survive in time?

 

I have a large pink moni that was almost 80% bleached. I just kept up with my water changes and such and its now bright pink. As long as you have color of some sort it has life.