Randall's assessor
Assessor randalli
Also known as Randall's Assessor Basslet, Randalli Assessor, Randall's Devilfish
SaltwaterFish
Care at a glance
- Temperature
- 73–81°F
- 23–27°C
- pH
- 8.1–8.4
- Adult size
- 3.1 in
- 8 cm
- Minimum tank
- 29 gal
- 110 L
- Temperament
- Peaceful
- Social behavior
- Social
- Swim level
- Middle
- Diet
- Carnivore
- Difficulty
- Easy
- Breeding
- Medium
- Rarity
- Rare
- Reef safe
- Reef safe
- Family
- Plesiopidae
- Origin
- Western Pacific from the Ryukyu Islands and the Philippines south to the Great Barrier Reef, near caves and overhangs.
Overview
Randall's assessor is a small, peaceful reef fish for a tank with plenty of rocky cover. It is easy to keep.
Did you know
Randall's assessor often hangs upside down beneath ledges, treating the roof of a cave as its floor.
Caring for the Randall's assessor
Give Randall's assessor a reef of at least 29 gal (110 L), with caves, ledges and plenty of shaded overhangs. With enough cover, it stays out where you can see it. It is shy and uses the caves for cover when startled.
Keep the water at 73 to 81°F (23 to 27°C) and a pH of 8.1 to 8.4. Feed small meaty foods such as mysis, enriched brine and finely chopped seafood.
It is peaceful and fully reef safe, defending only its own den. You can keep a small group in a large, cave-rich aquascape. Like its relatives, it is a mouthbrooder, and breeding it is moderately hard.
Good to know
Assessor randalli belongs to the family Plesiopidae, along with the comets and longfins. It is the third and least-known member of the assessor genus, and the least common of the three in the trade. Its blue body develops red accents with age.
In the wild
Randall's assessor lives in the western Pacific, from the Ryukyu Islands and the Philippines south to the Great Barrier Reef. It stays near caves and overhangs.
Weekly picks
Tank mates
The Randall's assessor is a 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.
Pajama cardinalfish
Sphaeramia nematoptera
Saltwater3.1 in (8 cm) · 29 gal (110 L)72–81°F (22–27°C)
Royal gramma
Gramma loreto
Saltwater3.1 in (8 cm) · 29 gal (110 L)72–81°F (22–27°C)
Yellow watchman goby
Cryptocentrus cinctus
Saltwater3.5 in (9 cm) · 20 gal (75 L)72–81°F (22–27°C)
Skunk cleaner shrimp
Lysmata amboinensis
Saltwater2.4 in (6 cm) · 20 gal (75 L)73–81°F (23–27°C)
Ring cowrie
Monetaria annulus
Saltwater1.2 in (3 cm) · 20 gal (75 L)75–81°F (24–27°C)
Pearly jawfish
Opistognathus aurifrons
Saltwater3.9 in (10 cm) · 29 gal (110 L)73–81°F (23–27°C)
Common questions
What size tank does a Randall's assessor need?
A Randall's assessor needs at least 29 gal (110 L). It spends most of its time in the middle.
What temperature and pH does a Randall's assessor need?
A Randall's assessor is comfortable at 73–81°F (23–27°C) with a pH of 8.1–8.4.
What does a Randall's assessor eat?
A Randall's assessor eats small meaty foods, such as mysis, enriched brine and finely chopped seafood.
How big does a Randall's assessor get?
An adult Randall's assessor reaches about 3.1 in (8 cm).
How does a Randall's assessor breed?
Randall's assessor is a mouthbrooder, like its relatives. Breeding it is moderately hard.
Related species
2.8 in (7 cm)29 gal (110 L)72–79°F (22–26°C)Blue assessor
Assessor macneilli
2.8 in (7 cm) · 29 gal (110 L)
2.8 in (7 cm)29 gal (110 L)72–79°F (22–26°C)Yellow assessor
Assessor flavissimus
2.8 in (7 cm) · 29 gal (110 L)
6.3 in (16 cm)55 gal (210 L)73–81°F (23–27°C)Marine betta
Calloplesiops altivelis
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Paracheilinus carpenteri
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3.1 in (8 cm)29 gal (110 L)72–81°F (22–27°C)Chalk bass
Serranus tortugarum
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3.1 in (8 cm)26 gal (100 L)73–81°F (23–27°C)Disco blenny
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