Emerald Crabs.
Valonia Algae bubbles can get too large for the Emerald Crabs to physically handle. When that happens, stick a pin/needle through the end of a long thin stick and pop them. The deflated bubbles can then be eaten by the Emerald Crabs.
Many people worry that popping Valonia spreads it. Truth is, it spreads all by itself anyway, so popping it is a good thing because Emeralds can then eat it.
Aloha,
Mark