Green Bubble Algae

Care Summary

Green Bubble Algae (Valonia ventricosa) forms large, smooth, iridescent green spheres on rock and glass. Individual bubbles can grow to marble-size or larger. Manual removal is the primary control — do NOT pop the bubbles in the tank as this releases spores and worsens the problem. Instead, carefully peel the entire bubble away intact and remove it. Emerald crabs (Mithraculus sculptus) are the best biological control. Outbreaks are typically triggered by elevated phosphate. Address the nutrient source first.