HELP!!! Seasons Greetings Montipora emergency!

[weagle117]

Sorry I had to send video.... couldn't figure out the "URL of my photo." Its in my picture library on my laptop. Anyway, I got this montipora @ 2 yrs ago. It was the size of a quarter. It has been growing beautifully to @ 9ins I think. Id break a piece now & then and it would even grow from those. @ 2-3 weeks ago I noticed the pale "growing" part on the edges were a little wider than usual. Then the pale started getting bigger and bigger. Now only the very center is still green and on the bottom left side there is a really nasty brown edge that looks completely dead. Water tested over the last few weeks has been normal except for phospates, which were 0.25. I've done water changes every 2 weeks (twice) with RO water. I had a problem with hairy green algae (husband felt sorry for the poor "little hungry fish" and was feeding them when I wasn't looking) which I have been picking off my green star polyps for about 2-3 weeks. My aquarium expert at my fish store gave me some white pebble looking phosphate eaters that I put in a sock in one side of my hanging back up filter (no filters though- just live rock) . He also sold me some captiv phos Fe by Continuum aquatics to put in the other side. He guarantees the phosphate problem should be gone in a couple of weeks. The green algae seems to be getting better. The only other problem I can think of is that my heater went out and the temp went to @72 degrees before I got the new heater in. That was @ a month ago. I can't imagine that that would cause a slow death to my montipora but you may know differently. Everything else living seems to be ok in the tank..... @10yr old tomato clown, 2yr old yellow tang, 2 blue yellow tail damsels, @6 yr old six line wrasse, a big brown tunneling goby (I think), snails, hermit crabs, flame scallop (put in tank @ 1week ago), mushrooms, colony of yellow polyps (see a little of them in video), pitiful green star polys nearly smothered by algae), small bird's nest coral, eagle eye zoas & 2 other very small zoas- don't know names) and a little colony of palys. Hope that is enough info. Let me know if I left anything out. I really would like to save at least a frag of my montipora. It really grew fast for a while & was beautiful! Could it be that there are not enough nutrients since I've hidden the food from my husband? And they don't have enough to eat? PLEASE send me any advice you can think of.... Thanks in advance!