Go to ReefTopia and get you 30-50 of the pincushions. You need a full platoon and not just a unit of them. Any less and they just take their sweet little time just to mock you. You can give them away when they mow it down in a few months... or they can stick around and keep your coralline in check. The urchins are not effective if you let your N or P rise too much... does not have to be at NSW, but cannot be too high either. If the N and P gets too high, they just really seem to slow down - if it gets really high, they will die. IMO, snails are a joke for a job like this. Fun fact, but these can live to be more than 100 years old, I guess. Other than moving around frags, they are my favorite algae eaters, are cheap at hardy.
Pincushion urchins do very well within a Reef Aquarium and control a variety of algae. We do our best to select interesting colors when collecting these. Size varies from golf ball to slightly larger when collected for the marine aquarium. Variation of colors.
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