Food-grade fish · warm-water · omnivore

Silver perch

Bidyanus bidyanus

Also known asBidyan · Silver grunter

beginner warm-water 40% dress-out
Harvest weight
1000 g
40 cm long
Days to harvest
365–730
from fingerling
Feed protein
32%
Optimum temp
26°C

Water parameters

Temperature
0102030
1530°C
pH
45.578.5
6.5–8.5
Hardness
0102030
5–25 dGH

Minimum tank: 300 L per individual at harvest size.

Feed and growth

Feed protein
32% target
Daily feed (warm)
1.30% of body weight
Daily feed (cool)
0.60% of body weight
Max density
45 g per litre

A 1000 g adult eats about 13.0 g of feed per day at optimum. 10 fish at adult size: ~130 g daily.

Legality

Rules vary by jurisdiction and change over time. Verify with your local fisheries or wildlife authority before stocking.

JurisdictionStatusNotes
New South Wales legal Native species; no permit required from licensed hatchery fingerlings verified 2026-05-13
Victoria legal verified 2026-05-13
Queensland legal verified 2026-05-13

Unlisted jurisdictions default to "check local regulations".

Origin and habitat

Endemic to the Murray-Darling basin of southeastern Australia, a mid-sized member of the grunter family Terapontidae. Wild fish usually run about 35 cm and 2 kg but can reach 61 cm and close to 8 kg; farmed fish are taken much smaller, around 400800 g. Silver perch live in warm, slow rivers, billabongs and floodplain lakes. The flesh is white, moist and mild, though it can pick up an earthy or muddy taint from algal compounds in still or green water, which is the species' main market weakness. River regulation, lost habitat and introduced competitors have cut wild numbers sharply: the Australian government reassessed the species in 2024 and lists it as Endangered under the EPBC Act, while the 2019 IUCN assessment rated it Near Threatened. It is one of the most widely farmed native fish in Australian aquaculture.

Climate and outdoor ponds

warm-water species
!Heating required in temperate
·Cooling required in temperate
Climate
subtropical (tolerates mild cooling)
USDA zones
8–13 (winter low around -12°C or warmer)
Heating needed
yes
Cooling needed
no

Care notes

A warm-water native well suited to Australian aquaponics, growing faster than golden perch or Murray cod and handling cooler water than barramundi. It does best around 2528°C within an operating band near 1530°C, and is hardy enough to ride out mainland winters without heating in most places; it even tolerates moderately saline inland groundwater. Farmed fish reach roughly 400800 g in 10 to 14 months on extruded pellet of about 32 to 35 percent protein, with feed conversion typically around 2 to 2.5 in well-run systems. Stock about {density:15}-{density:30}. Silver perch shoal and take tank culture better than the predatory natives, though aggression and lower survival appear at poorly chosen densities, so stocking needs care. They learn pellets readily when trained as fingerlings. Keep dissolved oxygen above about 4 mg/L, ammonia low and pH between 6.5 and 8.5. The recurring problem is off-flavour: fish can absorb earthy-musty algal metabolites from green water, so clean, well-filtered systems help, and purging in clean flowing water for several days before harvest clears most of it. Fingerlings are widely sold by Australian hatcheries, peaking in spring and summer, and the species is legal to farm across eastern Australia without special permits. For an Australian grower wanting a balanced native, silver perch is the best all-round pick.

Further reading