Kinda hard to tell with it closed up, but I agree that it is probably a tree coral (Nephthea). One other possibility would be a Kenya tree coral (Capnella).
I believe these are the same RO units that can be found at:
http://www.aquariumwaterfilter.com/
If so, I have one and they are GREAT!!! excellent customer service! I have the 100GPD and was very impressed with the quality of the unit.
Commonsense would tell me that anything going through the impeller of a pump would be dead...however....
My wife has a Biowheel filter on her 20L Reef. All water intering the filter is feed via a pump. I was doing maintenance for her and was prepared to replace the mechanical/carbon filter...
I purchased this product before I heard the prevailing wisdom on it. However, I did use it in my tank and my mushrooms and other softies were greatful. However, compared to other products that do the same thing, it is very expensive. A much better option would be to get some Golden Pearls (2...