It is a Hippo Tang (baby) and yes I have been feeding them the other options listed in my info.
All of my tank inhabitants LOVE the brine shrimp with spirulina. Most will pick at the Spectrum Life food, and none go for the seaweed. The only problem with not feeding them is that my clowns, firefish, and wrasse are strictly meat eaters. I am concerned about them not receiving food for too long.
Another question I have is how long can I leave a piece of seaweed in the tank before it will start turning my water?
As for the LR grazing, I see my angel nipping at the brown algae on the glass and the LR. But I never see my Tang nipping at the LR, also most of my LR still hasn't started growing the beneficial algae yet (then again most of it has only been in the display tank for 3 weeks now and it was originally bought uncured.