TankBud

Yellow firemouth

Thorichthys affinis

Also known as Affinis firemouth

FreshwaterFish

Yellow firemouth (Thorichthys affinis)

Care at a glance

Temperature
75–84°F
24–29°C
pH
7.0–8.2
Adult size
6.7 in
17 cm
Minimum tank
66 gal
250 L
Temperament
Mostly peaceful
Social behavior
Solitary
Tankmates
With caution
Swim level
Bottom
Diet
Omnivore
Difficulty
Medium
Breeding
Substrate spawner · Medium
Rarity
Rare
Family
Cichlidae
Origin
Lake Petén basin, Guatemala

Overview

The yellow firemouth is a firemouth relative from Guatemala that stays near the bottom, sifting sand and grazing. It is best with a little experience.

Did you know

The yellow firemouth and its relatives are named for the fiery red or orange throat a displaying fish shows off. That color flares brightest when a fish faces down a rival at the edge of its territory.

Caring for the yellow firemouth

Give a yellow firemouth or a pair at least 66 gal (250 L), with a soft sand floor to sift. Add driftwood, some flat stones and planted areas for cover. It does best in a calm, well-planted tank with open sand.

Keep the water moderately hard and near neutral, at 75 to 84°F (24 to 29°C) and a pH of 7.0 to 8.2. Thorichthys sulk and sicken in poor water, and they dislike stale, nitrate-heavy water. Keep up steady filtration and frequent water changes.

Feed sinking pellets, frozen bloodworm, brine shrimp and a little vegetable food. Keep it singly or as a single pair, which defends a small territory when spawning. It is mostly peaceful and leans on a gill-cover bluff rather than real fighting. Tank mates still need some care, so choose gentle, similar-sized community fish and nothing pushy.

It is a biparental substrate spawner. A pair guards eggs laid in the open and shepherds the fry together, and breeding it is only moderately difficult.

Good to know

Thorichthys affinis is a cichlid in the family Cichlidae, with gold flanks beneath a red throat. It is the Petén counterpart of the more familiar firemouth cichlid.

In the wild

The yellow firemouth lives in the clear, silty-margined lakes and slow rivers of the Petén basin, in northern Guatemala and nearby lowlands.

Common questions

What size tank does a yellow firemouth need?

A yellow firemouth needs at least 66 gal (250 L). It spends most of its time in the bottom.

What temperature and pH does a yellow firemouth need?

A yellow firemouth is comfortable at 75–84°F (24–29°C) with a pH of 7.0–8.2.

What does a yellow firemouth eat?

A yellow firemouth eats sinking pellets, frozen bloodworm, brine shrimp and a little vegetable food.

How big does a yellow firemouth get?

An adult yellow firemouth reaches about 6.7 in (17 cm).

How does a yellow firemouth breed?

A yellow firemouth is a biparental substrate spawner. The pair guards eggs laid in the open and shepherds the fry together. Breeding it is only moderately difficult.

Related species