Maroon Clownfish Breeding Guide

How to breed the Maroon Clownfish (Amphiprion biaculeatus): strong size dimorphism, substrate spawning, male egg tending, ~7 day hatch and rotifer-reared larvae.

Overview

Amphiprion biaculeatus (also placed in Premnas), the maroon clownfish, has successfully bred in home aquariums and shows the most extreme size dimorphism of the anemonefish. Like other clownfish it lays demersal eggs on cleaned rock and the male tends them. Its specialized host is the bubble-tip anemone (Entacmaea quadricolor).

Sexing

The species is a protandrous sequential hermaphrodite with a strict size-based hierarchy: the female is largest and the breeding male second largest, and the breeding male changes to female if the sole female dies. Females are among the largest anemonefish, growing up to 17 cm (6.7 in), while males are much smaller, usually 6-7 cm (2.4-2.8 in); this dramatic size gap makes the pair easy to recognize.

Conditioning

Maroon clownfish are usually found as a single mated pair rather than a group, so a bonded pair must be established carefully, ideally by raising a small juvenile (future male) alongside a larger fish that becomes the female. A mature, stable marine system and regular feeding bring the pair into spawning condition; rotifer and microalgae cultures should be ready beforehand.

Spawning Behavior & Trigger

As with other anemonefish, the pair cleans a flat rock near the anemone and the female deposits eggs there for the male to fertilize. Maroon clownfish defend the nest aggressively. The female can lay a large clutch (well into the hundreds), and the eggs are adhesive and attached to the substrate.

Egg & Fry Care

The male cleans, guards and fans the eggs. The eggs take around seven days to hatch, releasing pelagic larvae that must be reared in a separate larval tank. Newly hatched larvae are fed enriched rotifers and then graduate to baby brine shrimp once large enough, following the standard anemonefish rearing sequence.

Common Challenges

Maroon clownfish are the largest and most aggressive clownfish, so the female can dominate or harm an undersized or unready male; pair them with care. As with all anemonefish, the pelagic first-feeding larvae are the bottleneck and require live food of the correct size from hatching. The species is widely tank-raised and subject to selective breeding, notably the lightning morph with broken, jagged, honeycomb-patterned bars.