Hello everyone! Little update. After a month hes gained a ton of color, but NOT doing well. 2 weeks ago he became healthy enough to take his first walk around my tank. Since the tank is over 4ft deep he wasnt able to make it high enough if the water column in his weak state to reach stronger lighting and finallylayed down in the sand deep under a ledge without any lighting. I left him for 2 days hoping he would keep moving, but didnt.
After 2 days I pulled him from the bottom of the tank and put on a glass mounted ledge. Unfortunately grabbing him from the bottom of the tank under the ledge using. A long handled claw wasnt as gentle as I would have hoped. His old home (befor walking) had 60par, and the new ledge was approx 140par. Big change, but I hoped acceptable. 24 hours later he jumped off the ledge and back into the sand bottom in a crappy spot. I left him there for 2 days but it was obvious his health was DRASTICALLY deteriorating.
In a last ditch effort I took a spare light and put it directly against the glass nearest to him at the bottom of the tank. Within an hour he had turned to face it and tripled in size and vigor!! Whew. Fast forward to 4 days later. He still refused to bury his foot and simply layed on the sand with his mouth open.. not good, but he was reactive positively to the light and would move a few inches every day pushing to get the most possible light.
3 days later due to a mistake with my apex programming a wavemaker turned on and sucked him up into the mp10.

I figured all was lost. He was done. HOWEVER HE WONT GIVE UP!!!! 24 hours later he was nearly wide open again with only a dozen or so tenticles looking shorter than before the incident.
4 days later he still hasnt closed his mouth, but has pretty great movement and looks to be healing! I decided 48 hours ago to move him into a fluval 13.5 with the same light I had "revived"him with. The hope was that he could receive better care in this tank and his environment could be better controlled. Poor SOB is still active, but will not close his mouth or bury the foot.
I'm at a loss on next steps. Do I feed more? Feed less? Get stupid and poor skim mate into the tank for nutrients? Haha kidding.
Seriously. All tips or experience appreciated!
First image is right after the wave maker incident.
2nd image is in main DT with the side lighting.
3rd image is in the 13.5 fluval (****** little tank surprisingly!) Right after adding (I had buried foot).
4th image is after he moved elsewhere and wont bury the foot. Been there since.