I have had mine for about 10 months I would be aggreeing with the getting a healthy one, I know im in Australia but to add mine has gone through some hard conditions as well, as falling down the back rock wall of my tank for a day, having temp spike over 32 degrees cent not sure what F that is but yeh med to high lighting I have mine on sand they love it on there because the live rock I have found irritates them, oh and I use 150W MH and T5 combo.
Got mine about 4 cm by 2 cm now extends over 10cm they get big when happy.
Ill let you guys know how I go propagating them. But I havent seen any bacterial probs even at the shop i work, too bad for you guys.