Baby Betta Fish Care Guide: Fry to Juvenile Husbandry
Most hobbyists meet a juvenile Betta splendens when a shop labels a thumb-sized fish “baby betta” and prices it cheaper than the adults. Some are raising fry from a deliberate spawn. Either way, the baby betta fish stage demands feeding, water and housing rules that look almost nothing like adult care. This guide from Gensou Aquascaping at 5 Everton Park walks through fry-to-juvenile husbandry, week by week, with the protocols Singapore breeders use to push survival rates above 70%.
Defining the Life Stages
Day 1-3 the fry are still consuming yolk sac, glued to the underside of the bubble nest. Day 4-7 they free-swim and need food. Week 2-4 covers the microfeed phase. Month 1-3 sees rapid growth, body colour development and the first signs of male-female differentiation. Pet shops typically sell “baby betta” at week 8-12, when fish reach 2-3 cm and show identifiable fin shapes. Each stage needs different feeding and water management.
Tank Setup for Fry
Newly free-swimming fry live in a shallow grow-out — 20-30 litres at 8-12 cm fill height, bare bottom, gentle sponge filter only. Shallow water lets fry reach the surface to develop their labyrinth organ around week 3-4 without exhausting them. The Xinyou XY-168 Mini Bio Sponge Filter on the lowest air-pump setting moves enough water without sucking fry against the intake. Cover the tank tightly; fry chill instantly under air-conditioning, which collapses labyrinth development.
Temperature Stability
Hold 27-28°C without swing for the first eight weeks. Variations of more than 1.5°C in 24 hours kill labyrinth-stage fry outright. Singapore HDB ambient sits close to ideal but bedroom aircon is the killer; place the grow-out away from vents and add a 25W heater set conservatively. The Sunsun GW-25B Low Water Level Heater works in shallow tanks where standard heaters dry out.
First Foods Week 1
Fry mouths at day 4 are tiny — only microscopic foods fit. Newly-hatched baby brine shrimp (BBS) is the gold standard. Hatch your own with a brine shrimp hatchery or use the JBL Artemio Set. Feed BBS three to four times a day, just enough that fry bellies turn orange. Vinegar eels and microworms work as backup. Do not use fish flake powder — fry cannot digest it, and uneaten flake fouls the water in hours.
Transition Foods Week 2-4
By week three, fry handle slightly larger food. Continue BBS but introduce HIKARI First Bites as a powder dust on the water surface, plus daphnia for the larger fry. Crushed pellet from HIKARI Betta Bio-Gold ground between two spoons starts at week four. Feed five small meals a day rather than two large ones — fry stomachs are the size of a poppy seed.
Water Changes and Cleaning
Fry water fouls fast. Change 20% daily from week one through week four, drip-acclimating new water at the same temperature. Use a fine airline tube as a siphon to vacuum debris from the bare bottom without sucking fry. Treat all replacement water with Seachem Prime at 0.5 ml per 20 litres to neutralise PUB chloramine. Skipping this kills fry within an hour — chloramine penetrates labyrinth tissue directly.
Jarring and Separation
Around week 8-10, males start sparring. The traditional response is “jarring” — moving each male to its own 1-2 litre container. This is labour-intensive: jars need 50% daily changes and stable temperature, but it prevents fin damage during the most rapid growth phase. Smaller breeders use the UP AQUA D-016 Betta Box as a divider hung in a larger heated tank, sharing one filter across multiple compartments.
Identifying Sex and Form
By week 10-12, males show longer ventral fins and the start of a beard membrane below the gill plate. Females stay shorter-finned and develop a small white “egg spot” between ventrals and anal fin. Tail form locks in by week 16 — veiltail droop, halfmoon spread or plakat short-fin become identifiable. Cull selection happens here for breeders aiming at competition standard; pet-trade fry are typically sold mixed-sex at week 8-10.
Tannin Support and Stress Reduction
A piece of ANS Catappa Leaves Small in the grow-out releases tannins that mimic the fry’s natural blackwater habitat. Tannins lower bacterial pressure, soften water and tint it tea-coloured — fry exposed to catappa from day one show better fin development and lower jumper losses than those raised in clear water. One small leaf per 10 litres lasts three to four weeks before replacement.
Singapore Sourcing of Baby Bettas
Local pet shops sell “baby betta” specimens at SGD 4-8, usually mixed colour and unsexed at week 8-10. Iwarna, C328 and Serangoon North shops rotate stock weekly. For deliberate breeding stock, Carousell breeders sell sexed pairs at SGD 25-50 and identified fry by spawn at SGD 6-12 each. Live BBS cysts and grow-out gear are stocked across fish food and feeding and breeder supply listings. Check fry bellies for full orange colouration before purchase — empty bellies indicate stalled feeding and predict losses.
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Still Have Questions About Your Tank?
Drop by Gensou Aquascaping — most walk-in questions get answered in under 10 minutes by someone who has set up hundreds of tanks.
5 Everton Park #01-34B, Singapore 080005 · Open daily 11am – 8pm
