Brook stickleback
Culaea inconstans
FreshwaterFish
Care at a glance
- Temperature
- 50–68°F
- 10–20°C
- pH
- 6.5–8.0
- Adult size
- 1.8 in
- 4.5 cm
- Minimum tank
- 20 gal
- 75 L
- Temperament
- Aggressive
- Social behavior
- Solitary
- Tankmates
- With caution
- Swim level
- Middle
- Difficulty
- Difficult
- Breeding
- No record
- Rarity
- Very rare
- Family
- Gasterosteidae
- Origin
- United States, Canada
Overview
This is a territorial, scrappy fish, especially the males at breeding time, so it's best kept on its own or with careful coldwater tankmates in a 75 liter or larger tank. It tends to hang in the middle of the water and defend a patch. It's a poor match for the usual community fish and won't take dried food well, so plan on live or frozen bloodworms, brine shrimp, and daphnia. It's a difficult fish overall because of the cool water and feeding demands.
In the wild
The brook stickleback lives in cool, slow streams, small rivers, and ponds across the northern United States and Canada, in clear water with plants for cover. This is a coldwater fish, not a tropical one, so it needs a cool tank, roughly 10 to 20 C, and usually a chiller in a warm room. Give it dense planting and quiet water rather than strong flow.
Good to know
Culaea inconstans is the only species in its genus, in the family Gasterosteidae. It's a small fish, around 4 to 5 cm, and instead of scales it has bony plates and small spines along the back. It's a nest builder: the male weaves a nest from plant material held together with a glue-like secretion, then guards the eggs until they hatch. The IUCN lists it as Least Concern.
Did you know
The male builds a barrel-shaped nest off plant stems, gluing it together with a sticky protein his kidneys produce, then fans water through it to keep the eggs oxygenated. He'll even patch and rebuild the nest if it gets damaged while he's guarding it.
Common questions
What size tank does a Brook stickleback need?
A Brook stickleback needs at least 20 gal (75 L). It spends most of its time in the middle.
What temperature and pH does a Brook stickleback need?
A Brook stickleback is comfortable at 50–68°F (10–20°C) with a pH of 6.5–8.0.
How big does a Brook stickleback get?
An adult Brook stickleback reaches about 1.8 in (4.5 cm).
Related species
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Pethia padamya
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