Not a senior reefer here, but i try to help
Next time you buy Yuma try to put it in the bottom shaded area of the tank & slowly move it up ..so it gets used to the light..
Yuma require moderate light & current...too strong & it might melt, too strong current & it will detach itself for the rock. So its important to give it the right conditions.
So far I have no problems with Yuma Ricordea & Yuma Florida I find it difficult to keep too.
Sanjay
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