Trachyphyllia help

[HarlequinTuskReef]

So I have a trachy I've had for a few years. When I bought it was very inflated and had nice color. After a few months it shrunk way down and would occasionally open up. Now the thing hasn't changed in like 1 yr but is still alive somehow. This thing has never really accepted food and now does nothing when I try and feed. Its been in two tanks, a 200 gallon and a 600 gallon system (current system). These tanks were both mixed reef tanks where I keep a mix of acros and lps. Par is around 100 to 150 in the sand. Tank is 10 ft x 3 ft x 3 ft with currently 3 orphek v4 running at max 100%. I'm upgrading to 5 here very shortly and going to try and adjust output to maintain same par levels. Parameters are alk:7.7 dkh, cal: 486 ppm, mag:1211 ppm (raising this currently). Any good ideas for something to try? Pick 1 is current, pic 2 is a old partly inflated pic.

 

[Spare time]

Your alkalinity is a little on the lower end. Maybe getting that up might help. From what I can find online most places are recommending an alk a little higher than yours.