So we've ruled out, hermits, possibly the clowns. Lighting/depth sounds fine. (I forgot to mention that my one 250w MH is in the center of a 60gal cube, and the goni is located on the 'outskirts' of the light beam. So it's not directly located underneath the bulb.)
Btw, that's great the the color has improved! However, if you didn't believe the goni is bleached, why did you move it into the shade, (unless the flow was too much in that same spot)?
Also, target feeding this particular coral seems to be important-especially now.
Here's what I would do:
Take out some frozen cyclopeez and mash it with a spoon (I used a tiny mortar & pestle dedicated to the aquarium) to get the 'juice' from the cyclopeez mix it with a drop of selcon if you have it. Smashed oyster eggs work great in eliciting a feeding response from these corals too.
Turn off the aquarium pumps/powerheads/airstones etc (anything that moves the water). Feed all the fish first so they are busy. Then take a pipette and VERY GENTLY puff (not blow) the juice in the goni's direction, trying to get each polyp a little juice. Do this 3-4 times per week in the beginning.
Watch closely for a feeding response...it will be difficult at first as you are just feeding 'juice.' But eventually, you will notice the polyps pulling in about halfway down, tentacles moving toward the mouth, other polyps moving towards the polyp you are targeting-to share the food. Even though you are feeding 'juice' they will be getting some nutritional value out of it.
Don't move the coral around during this time. Resist the urge to keep moving it. These corals tend to remain shy about coming out when you disturb them, so I would not suggest taking them out of the aquarium every time you feed it. It needs to feel secure enough to attempt to come out and feed.
Then begin to use the cyclopeez juice and whole cyclopeez, plus small amounts of thinly shaved mysid or table shrimp (some of the Rod's food would probably work too), something where you can see the food being grasped and held onto by the polyp. Then you will know that it is trying to actively capture it's food. (At this point, the food should be slightly paste-like so that it remains on the polyp.)
Once you are sure that the goni is trying to feed, you could take a clear plastic Coke 1 or 2L bottle (cut the bottom off and take the cap off) and place it over the goni without touching it (you don't want to tear the tissue). Now you should be able to feed the goni with the pipette by squirting th food through the mouth of the bottle and leave it for about 20 mins. This keeps the food close to the coral giving it a chance to feed without the food being washed away or without being stolen by other animals in the tank.
I was very skeptical at first and didn't think ANYTHING was happening when I began to feed using this method. So I took out my DSLR camera and watched on the live view function zoomed in 7-10x with a macro lens. But I witnessed the coral (without moving any of it's tenacles) very slowly, through minute movements, move a cyclopeez towards it's mouth and swallow the food! But it took some time.
I think your coral can be encouraged in it's health, if you will take the time now to baby it a little.
I hope this helps! JAM
PS-Lowredranger, post a pic, let's have a look.