TankBud

Saddleback clownfish

Amphiprion polymnus

Also known as Saddleback Anemonefish, Yellowfin Anemonefish, Brownsaddle Clownfish

SaltwaterFish

Saddleback clownfish (Amphiprion polymnus)
Jens Petersen · CC BY-SA 3.0

Care at a glance

Temperature
75–82°F
24–28°C
pH
8.1–8.4
Adult size
5.1 in
13 cm
Minimum tank
40 gal
150 L
Temperament
Mostly peaceful
Social behavior
Social
Swim level
Middle
Diet
Omnivore
Difficulty
Medium
Breeding
Egg layer · Hard
Rarity
Rare
Reef safe
Reef safe
Family
Pomacentridae
Origin
Silty lagoons and harbors of the Indo-Pacific Coral Triangle, from the Philippines to northern Australia

Overview

The saddleback clownfish is an anemonefish for the middle of a reef tank. It is a step up from the easiest clownfish and best with a little experience.

Did you know

The saddleback clownfish's white saddle is unique among common clownfish. It is a single slanted bar rather than the vertical stripes most other Amphiprion species wear.

Caring for the saddleback clownfish

Give a saddleback clownfish at least 40 gal (150 L). It is reef safe and does fine without an anemone, though a saddle carpet anemone is its natural match if you want to keep one. Captive-bred stock adjusts to aquarium life quickly, while wild-caught fish can take months to settle in.

Keep the water at 75 to 82°F (24 to 28°C) with a pH of 8.1 to 8.4. It is an easy omnivore that takes mysis, krill, enriched brine shrimp, flake and pellet food. Add some spirulina if it is not grazing on algae in the tank.

The saddleback clownfish is one of the calmer anemonefish toward other species. It is territorial, though, and will chase off other clownfish or anything that threatens its anemone. Keep it singly or as a bonded pair.

Unlike most clownfish, males and females are close to the same size. That may help both partners dart for cover when a predator approaches the anemone. It is a protandrous hermaphrodite that reaches sexual maturity at around 1.5 to 2 years old. Its eggs hatch in 7 to 10 days, and breeding it is hard.

Good to know

The saddleback clownfish, Amphiprion polymnus, takes its name from the broad white saddle across its midsection. Its body runs from dark brown to yellow-orange.

In the wild

The saddleback clownfish lives in silty lagoons and harbor areas of the Indo-Pacific Coral Triangle. Its range runs from the Philippines to northern Australia and the Ryukyu Islands, generally in murkier water than many other clownfish tolerate. It is a host specialist, pairing almost exclusively with the saddle carpet anemone and occasionally the sebae anemone.

Symbiotic relationships

Clownfish and their host anemones

A clownfish lives inside an anemone that stings and eats other fish its size. Its mucus coat keeps the anemone's stinging cells from firing, and a new fish builds that protection up over hours of brief touches. The fish gets a refuge no predator will follow it into and a nest site at the anemone's base. The anemone gets a guard that drives off the butterflyfish that would graze its tentacles, a steady supply of nitrogen from the fish's waste, and water movement at night, when the fish fans its fins among the tentacles and the anemone takes up more oxygen. Only ten anemone species host clownfish in the wild, and each clownfish species uses its own short list of them.

Captive-bred clownfish have never seen an anemone and do not need one; they settle for a coral, a powerhead or a corner of the tank. If you want the pairing, the anemone is the harder animal by far and goes in first, into a mature tank with strong light and stable water, at the tank size its own profile lists. The bubble tip anemone is the hardy host, and the one most clownfish accept in captivity even when it is not a natural host, so a clownfish profile lists it as the usual tank host where that is the case. The sebae, magnificent and carpet anemones are marked difficult, and the carpets eat fish. Expect a paired clownfish to defend its anemone against everything else in the tank.

Every symbiotic relationship in the catalog

Weekly picks

Tank mates

The saddleback clownfish is a mostly peaceful, social species that keeps to the middle. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.

Check the full mix in the stocking calculator

Common questions

What size tank does a saddleback clownfish need?

A saddleback clownfish needs at least 40 gal (150 L). It spends most of its time in the middle.

What temperature and pH does a saddleback clownfish need?

A saddleback clownfish is comfortable at 75–82°F (24–28°C) with a pH of 8.1–8.4.

What does a saddleback clownfish eat?

A saddleback clownfish is an easy omnivore that takes mysis, krill, enriched brine shrimp, flake and pellet food. Give it some spirulina if it is not grazing on algae in the tank.

How big does a saddleback clownfish get?

An adult saddleback clownfish reaches about 5.1 in (13 cm).

How does a saddleback clownfish breed?

A saddleback clownfish reaches sexual maturity at around 1.5 to 2 years old, and its eggs hatch in 7 to 10 days. Breeding it is hard.

Related species