It should work well for you guys. I emailed back and forth with Seachem's tech support. I was wondering why Seachem never came out with ferric oxide since everyone else had. Basically, it's an inferior product to the aluminum oxide.
All the post you hear of being negative to leather corals is more likely due to rapid phosphate removal than the aluminum like people post. Seachem even ran their own lab grade test on it.

Like any other product start small and work your way up. I love it. It doesn't clump. It's spherical so it has a large surface area and you get great water passage through it. I like I can run it in a bag and not need a reactor.