How to Take Care of a Betta Fish Guide: First-Week Plan
Caring for a betta fish starts with a 19-38 L cycled tank, a low-flow sponge filter, a tight-fitting cover, dechlorinated water and a feeding schedule of two-to-three pellets twice daily with one fasting day weekly. Get those five elements right and the fish thrives for three to five years. The phrase how to take care of betta fish deserves a structured first-week plan because the early days set up health for the rest of the fish’s life. This FAQ from Gensou Aquascaping at 5 Everton Park walks through day one to day seven for a new betta in a Singapore HDB flat.
Day Zero — Tank Setup Before Buying the Fish
Buy the tank at least one week before the fish. A 19-38 L tank from aquarium tanks and cabinets with a tight-fitting lid, sponge filter, soft substrate and live plants gives biological filtration time to establish. Skip the tiny 3-5 L bowls sold as ‘betta vases’ — they cannot hold stable water chemistry. Plant a few easy stems like Anubias, java fern and floating frogbit, and run the filter for seven days before introducing the fish.
Day One — Acclimation
Float the bag in the tank for 15 minutes to equalise temperature. Open the bag and add small amounts of tank water every five minutes for 30-45 minutes. Net the fish out of the bag and into the tank — never pour pet-shop water in, as it carries pathogens. The fish will sit motionless for 10-30 minutes; this is normal. Lights stay off for the first 24 hours.
Day Two — First Feed
Offer one or two small pellets from a quality betta food brand. Many bettas refuse food on day two — that is fine. Wait until the next day rather than dropping more food in. Uneaten pellets pollute small tanks fast. By day three or four the fish should accept pellets readily. If refusal continues past day five, check water parameters before assuming sickness.
Day Three — Water Test
Test ammonia, nitrite, nitrate and pH with a liquid kit from water testing. Ammonia and nitrite should read zero in a properly cycled tank; nitrate up to 20 ppm is fine. If ammonia or nitrite show any reading at all, do a 30% water change with dechlorinated tap water and retest the next day. Strip-style tests are fine for quick checks but liquid kits are far more accurate.
Day Four — Establishing Routine
Set the lights on a 10-12 hour timer to mirror Singapore daylight. Two pellets in the morning, two in the evening, leaving 8-10 hours between feeds. Watch the fish for 10 minutes after each meal — active investigation of the substrate and confident swimming patterns mean it is settling well. Hiding constantly suggests stress; check the heater, filter flow and tank placement.
Day Five — Heater and Temperature Check
Singapore HDB ambient runs 28-32°C, which suits bettas perfectly without a heater. If your tank sits in an aircon-cooled bedroom and drops below 24°C overnight, add a 25W preset heater from heating and cooling. Stable temperature matters more than the exact number — swings beyond 3°C in a day cause stress. A small aquarium thermometer stuck to the glass keeps you honest.
Day Six — Observe Behaviour
By the end of week one a healthy betta should explore the entire tank, build a small bubble nest at the surface, flare briefly at its reflection, and eat with enthusiasm. Persistent fin clamping, hanging at the surface gulping air constantly, refusing food, or hiding behind the heater are warning signs. Mild fin nipping from transport stress is normal and heals in two to three weeks with clean water.
Day Seven — First Water Change
A 25% water change with dechlorinated tap is the right end-of-week task. Use a small siphon to vacuum debris from the substrate and refill with temperature-matched water dosed with a water conditioner. Seachem Prime, Tetra AquaSafe or API Stress Coat all neutralise PUB chloramine — 1 ml per 38 L is the standard dose. Repeat 25% changes weekly going forward.
Common First-Week Mistakes
Adding too much food, adding tankmates immediately, dosing ‘pH down’ chemicals, using bowl-sized tanks, skipping the heater in aircon rooms, and pouring in pet-shop bag water all happen frequently. Each one stresses the fish or pollutes the volume. Stick to the plan above for week one and resist the urge to tinker. Adjustments come in week three and beyond, once you know your individual fish’s preferences.
Sourcing Bettas in Singapore
Iwarna, C328 and Petopia stock pet-quality bettas at SGD 8-25. Specialty breeders on Carousell offer show-grade halfmoon, koi and dragon scale strains at SGD 30-150. Avoid imported wholesale bettas from supermarket pet sections — they often arrive stressed and parasitised. Visit the shop and watch the fish flare and feed before buying.
Building Beyond Week One
Once the first week settles, week two introduces dim lighting variations, week three adds enrichment items like Indian almond leaves and ceramic caves, and week four can introduce shrimp tankmates if temperament allows. The first week is the foundation. Get it solid and the next three years are easy.
Related Reading
emilynakatani
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
