Got 5x of these black urchins as hitchhikers on my live rock. They have done wonders mowing down my hair algae infestation, but I have my nitrates/phosphates under control and I worry they are going to starve - particularly as they continue to grow (they all came in as hitchhikers smaller than a dime). Now they are around 1” across. If you’re interested, I’m happy to give away if you want to swing by to pick up. Located in San Francisco.