Sorry to hear that.
sps are fairly picky,
try to up your KH levels to 9, do it slowly but get on it, Ph is ok but you would want that at 8.3
when you say phosphate 0 as of 0.00 or 0.01 or 0.02 cause not having any phosphate also not good for corals as they need a little.
Also can you please tell me what your Led settings are and how long, it might be that your par may be too much, and how far up is your led light from the top of your water line?
your water is on the cooler side bring that up to 78f-79f degrees, for you that will be 26 celsius
Im willing to bet that your Par is probably too strong for the sps corals,
acans, and leaherheads corals can handle many variations of things.
Bring your ai as follows
led must be at least 12'' to 14'' high from the water line
set your Uv 50%, Violet 50%, Royal 56%, Blue 56%, Green 7%, Red 7%, White 15%
no more then 9 hours.
I promise you if you do these steps you will start to see some positive things in your tank,