For what it's worth-I have both of those corals in my tank and I don't add anything for them. I do have some filter feeders that I feed with marine snow, so I figure that if anything, they probably benefit from that, combined with regular pwc
's every week.
My kenya tree will drop a branch every now and then....it surfs around the tank for a day or so and attaches itself to some lr
. I started with one kenya tree and I now have 5 of them.
And, btw, cmor is more than right about the xenia....it will go nuts unless you monitor it.