Haven't updated this for a few months.
A lot has happened during this time. I lost all my acro to AEFW and red bug.
I also lost my jawfish as it jumped through the egg crate onto the floor.
At the time I didn't know what was causing the my coral death. All the parameters checked out fine. Thought maybe the foam background was leaching some chemicals.
So I decided to change it out and replace it with acrylic.
I also took out the old fine sand and replace with more granule sand.
The rock work got a major renovation as well.
After the change, my tank had a mini cycle and got some algae problem.
Here is the FTS after the change.

See the severe brown film covering the sand bed which is also crawling on the rocks.
At first I thought it was cyano, but later realized it is dino because the film got stringy. It is even clinging on some of my fish's dorsal fin. I hope it won't kill my fish.
I started to do more water change. Tried to cut the excess nutrient in the tank. Cut down on the light period. Siphon as much as possible. But the dino is just so hard to get rid off. I can swear that minutes after I siphon it out, it comes right back.
With all that effort, I am able to keep a little under control.

But there is still quite a bit of. My purple death is extremely unhappy and is all closed up.
I am waiting until end of November before adding any more acro species because of the AEFW. Hopefully by that time, I can have the dino taken care of.