Soooooo.... I've had a long-spine urchin in my tank for a few months.
He typically just hung out in a cave on the back of a rock and I hardly ever saw him move. I could see his spines sticking out so it was cool though. Well over the past 2 weeks or so he's been out almost constantly... He moves all over the place and really it's kind of cool to see him fit into cracks you would never think he could fit into due to his spines sticking out in all directions. Well, my concern is that he's recently developed a taste for coralline algae, and he's pretty handy at dispatching colonies of it.
The trouble is that I really like my coralline algae, and it's beginning to really take hold in my tank. Sometimes he just leaves these little white X-shaped bite marks all over, but other times the entire "crust" of coralline is gone down to bare rock...
Well, to get to the point, I like the algae, and I like the urchin too....
So my question is: What do you do to get coralline algae to grow faster?
I don't really have much for other types of algae (I don't know if that's a good thing, or a bad thing...) in the tank. I've heard "purple up" is a good product?
I would appreciate any suggestions if you have experience caring for a longspine urchin!