Paradise threadfin
Polynemus paradiseus
FreshwaterBrackishFish
Care at a glance
- Temperature
- 75–82°F
- 24–28°C
- pH
- 6.5–8.0
- Adult size
- 9.8 in
- 25 cm
- Minimum tank
- 75 gal
- 285 L
- Temperament
- Mostly peaceful
- Social behavior
- Social
- Tankmates
- With caution
- Swim level
- Bottom
- Diet
- Carnivore
- Difficulty
- Difficult
- Breeding
- No record
- Rarity
- Very rare
- Family
- Polynemidae
- Origin
- South Asia, South East Asia
Overview
The paradise threadfin is a peaceful, active fish for the bottom of a large tank with some salt in the water. It is a demanding fish best left to experienced keepers.
Caring for the paradise threadfin
Give a group of paradise threadfins a large, open tank of at least 75 gal (285 L). They are active swimmers that feed along the bottom, so they need open sandy floor and few obstacles. Keep the water clean and well filtered.
Paradise threadfins can survive in fresh water, but most keepers find them delicate unless a little salt is added. A low to moderate brackish strength keeps them healthiest. Give them warm, hard water at 75 to 82°F (24 to 28°C), with a neutral to alkaline pH of 6.5 to 8.0.
Feed meaty foods such as brine and mysis shrimp, chopped prawn, mussel and earthworm pieces. Offer live foods at first if needed.
The paradise threadfin is social, does no harm to its own kind and is best kept in a group. It is gentle toward tank mates too. Its long threads are easily nipped, though, so avoid fin-nippers and pushy fish. Its breeding is undocumented in aquariums.
Good to know
The paradise threadfin belongs to the family Polynemidae, the threadfins. Its common name comes from the long, free filaments that hang from the base of each pectoral fin.
In the wild
The paradise threadfin lives in the tidal rivers and estuaries of South and Southeast Asia. It is a euryhaline fish, moving through murky, brackish water and returning to fresh water to spawn.
Common questions
What size tank does a paradise threadfin need?
A paradise threadfin needs at least 75 gal (285 L). It spends most of its time in the bottom.
What temperature and pH does a paradise threadfin need?
A paradise threadfin is comfortable at 75–82°F (24–28°C) with a pH of 6.5–8.0.
What does a paradise threadfin eat?
A paradise threadfin eats meaty foods such as brine and mysis shrimp, chopped prawn, mussel and earthworm pieces. Offer live foods at first if it needs them.
How big does a paradise threadfin get?
An adult paradise threadfin reaches about 9.8 in (25 cm).
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