Flower pots are a little hard to keep. They need to be spot fed. You can try to make a feeding dome out of the top of a 3 liter bottle, put it over the coral and inject food into the bottle so the food stays around the coral. Leave it for 15 min. or so then remove the bottle. You will need to do this on a regular basis.
You also may want to try an iodine dip.

Other than that I would say give it to someone that can save it.

Good luck. Hope it turns out well.