Urchin not eating hair algae

[carpetlover]

I recently borrowed a tuxedo urchin to clean my live rock of hair algae, but he doesn’t seem eat much of it. He’s even carrying some macro on the back, so I think he’s happy. Or do they mow a really thin line through the rock? Hmm

 

[JosephM]

I personally have a short spine urchin that has worked on the rock somewhat. He does mow it down all the way to bare rock but he's not too crazy. I just picked up a sea hare and IMO they are the best thing you can get for GHA. He was gone crazy on that stuff and I'm already seeing a different 12 hrs in