Fossorochromis rostratus Breeding Guide

Breeding Fossorochromis rostratus, a large sand-sifting Lake Malawi hap that feeds by sifting sand and broods its eggs and larvae in the female's mouth.

Overview

Fossorochromis rostratus is a large haplochromine cichlid endemic to Lake Malawi, growing up to 24.4 cm (9.6 in) in total length. It feeds on small invertebrates that are often caught by sifting mouthfuls of sand, a habit that ties it to open sandy areas of the lake.

Sexing

The species is sexually dimorphic; dominant males develop the strongest nuptial colour, in line with the Lake Malawi haplochromine pattern, while females and juveniles remain plainer. The most strongly coloured fish in a group are mature males.

Conditioning

Condition broodstock on small invertebrate-based foods that match its sand-sifting diet, and maintain stable, firm, alkaline rift-lake water. A deep sand bed lets the fish express natural sifting behaviour and supports good condition.

Breeding Setup

Because of its large adult size and sand-sifting habit, the species needs a spacious tank with a deep open sand substrate. Keep one male with several females so courtship is divided across the group, with ample open sand for spawning.

Spawning Behaviour & Trigger

In this species brood care is highly developed, with the eggs and larvae being mouthbrooded by the female. After the eggs are fertilised the female collects them into her mouth, following the maternal mouthbrooding pattern of Lake Malawi haps.

Egg & Fry Care

The female incubates the eggs and larvae in her buccal cavity, typically for around three weeks as is usual for the group, before releasing the free-swimming fry. Brood care in this species is described as highly developed, so a carrying female is best left undisturbed, or moved to a quiet maturation tank with a sand bed, to avoid premature release of the brood. Released fry grow on well with frequent small feeds over fine sand that lets them begin natural sifting behaviour early.

Common Challenges

The main requirements are a large tank with a deep open sand bed, since the fish naturally takes in mouthfuls of sand to extract the small invertebrates it feeds on, and the firm alkaline water of Lake Malawi. A fine sand substrate lets the fish sift without abrasion and supports the highly developed brood care described for the species. As a maternal mouthbrooder the holding female stops feeding while incubating and should not be disturbed, so condition broodstock well before spawning to maintain her through the brooding period.