Aiptasia pallida (Glass Anemone) Reproduction & Pest Control Guide

How the pest glass anemone Aiptasia pallida spreads explosively by pedal laceration and gonochoric spawning, why it harms reef tanks, and how to control rather than cultivate it.

Overview

Aiptasia, commonly called the glass anemone, is a pest in reef aquaria. The well-studied Aiptasia pallida (now usually placed in Exaiptasia) hosts zooxanthellae and reproduces both asexually and sexually. According to Wikipedia it is problematic because it is stressful to surrounding coral and can occasionally sting fish and desirable invertebrates. It should be controlled, never deliberately cultivated.

Reproductive Mode

Aiptasia reproduces both asexually and sexually. Asexual reproduction is by pedal laceration; sexual reproduction in A. pallida is gonochoric, meaning separate sexes. Wikipedia notes that sexual reproduction depends on lunar cycles and low environmental stress, while asexual spread can occur continuously.

Asexual Propagation

Asexual spread is explosive. Wikipedia states that small segments separate from the pedal disc and that a single cell can be enough for a new Aiptasia to form, with new polyps typically developing within 14 days as genetic clones. Critically, attempts to remove it often inadvertently create more, because new polyps regenerate from remnants left behind.

Sexual Reproduction

During spawning, anemones release gametes into the water where fertilization occurs, and larvae develop as free-swimming planulae before settling and metamorphosing. Newly produced larvae are aposymbiotic, meaning they do not yet contain symbionts. This pelagic broadcast pathway is depended on lunar timing and low stress.

Common Challenges

Manual removal usually fails because fragments regenerate. Biological control uses peppermint shrimp and the nudibranch Aeolidiella stephanieae (formerly called Berghia verrucicornis), described by Wikipedia as one of the best predators for Aiptasia; some filefish and butterflyfish also eat the polyps but may harm desirable organisms.