My battle with dinoflagellates

[Dash]

I love my tuxedo urchin. Spike is a nice small fellow & doesn’t cause too much trouble (I tried a beautiful white urchin that grew enormous in a couple of months & he disrupted things so much that I took him back to JL). Sometimes I move him onto a rock that needs cleaning and he’ll do it haha. He’s also been with me since the beginning so around 3 years old now at least. I don’t have big long clumps of HA though, just small patches here & there. He scrapes rock clean, leaving a white trail