My discosoma mushrooms have been in my tank for 5 months (tank is 8 months old). They have a few new heads. Recently, over the past few weeks, I've noticed that my mushrooms look very bad and not as colorful as they used to be. I've been checking the parameters weekly and haven't noticed any changes. I haven't made any changes to the lighting settings either. All the other corals in the tank (soft/LPS) seem to be doing well. What could be the issue? Many thanks in advance!