Care

Betta Feeding: What to Feed, How Often, How Much

A varied diet built on high-protein pellets, with frozen and live supplements twice a week. One feed per day, one fast day per week. The math on overfeeding.

Published Reading time 4 min
A halfmoon plakat (HMPK) male betta combining short fins with 180-degree spread.
A halfmoon plakat male. A fish this color-saturated comes from a high-protein insect-and-fish-meal diet, not from flake food. Photo: Ar-betta via Wikimedia Commons, CC BY-SA 4.0.

Feed an adult betta four to six small pellets once per day, with one full fast day per week. Staple diet is a high-protein sinking or slow-floating pellet (40%+ protein, fish or insect meal listed first). Supplement twice a week with frozen brine shrimp, daphnia, or bloodworms. The 2022 laboratory-care review (PMC9334006) calls overfeeding the primary welfare issue in research betta colonies, and the same pattern shows up in living rooms.

What bettas actually eat

Wild Betta splendens in an Aceh rice paddy eats mosquito larvae, bloodworms (chironomid larvae), daphnia, cyclops, and whatever else fits in a fish the size of a thumb. Zero plant matter. They’re obligate insectivores.

A pellet that mimics this is 40 to 50% protein from fish meal, whole fish, or insect meal (black soldier fly larvae meal has become common). The first ingredient matters. “Fish meal” first is good. “Wheat flour” first is cat food dressed up.

A cluster of young betta fry photographed in a shallow rearing tank.
Young fry. Between week 4 and week 8 they need BBS and microworms three to five times daily to reach this body mass. Photo: ZooFari via Wikimedia Commons, CC BY 3.0.

The short list of pellets worth buying

  • New Life Spectrum Betta Formula. 45% protein, krill meal first. This is the boring correct answer. $8 for a 1 oz jar, lasts 6 months feeding one fish.
  • Fluval Bug Bites Betta. Black soldier fly larvae first, 40% protein. Newer product, good ingredient profile. Floats briefly then sinks.
  • Hikari Betta Bio-Gold. 45% protein, a legacy product, consistent quality.
  • Omega One Betta Buffet Pellets. 42% protein, whole salmon first. Smells of actual fish, which is a good sign.

Skip the grocery-store generic betta pellets. The ingredient list usually starts with wheat, and the fish either refuses them or eats them and bloats.

The feeding schedule

DayMeal
Monday4-6 pellets
Tuesday4-6 pellets
Wednesday3-5 frozen bloodworms OR brine shrimp
Thursday4-6 pellets
FridayFast
Saturday4-6 pellets
Sunday3-5 frozen daphnia OR brine shrimp

That’s six feed days and one fast day. On feed days, the fish eats within 30 to 60 seconds and the water stays clean.

How much is too much

A betta’s stomach is roughly the size of its eye. Four to six 1 mm pellets is about right. More than that and you see bloat: a visibly rounded belly that doesn’t slim down by the next morning. Chronic overfeeding produces the classic pet-store obese betta with a sagging ventral line and constipation-linked swim-bladder episodes.

Uneaten food is the second biggest ammonia source in a tank after fish waste itself. If you drop eight pellets and the fish eats five, two of those sink into the substrate and rot. That’s a 20% ammonia contribution with no fish benefit.

Frozen vs live vs freeze-dried

Frozen is the right default. Frozen brine shrimp, daphnia, and bloodworms retain moisture, don’t transmit disease (the freezing kills parasites on bloodworms), and thaw in a shot glass of tank water in 90 seconds. Buy Hikari or San Francisco Bay brand cubes.

Live is the gold standard but a logistics project. Live blackworms, brine shrimp, and daphnia are excellent protein and give the fish a foraging stimulus. Risk: wild-caught live food can carry parasites. Hobbyist-grown cultures are safer. A small live blackworm colony lives in a Tupperware in the fridge and feeds a betta for months.

Freeze-dried is a distant third. Dehydrated chitin swells in the gut. Linked to constipation and swim-bladder issues. Occasional treat at most, and only if pre-soaked in tank water for two minutes before feeding.

Fry and juvenile feeding

Fry under 4 weeks need live microorganisms: infusoria for the first 4 to 5 days, then newly hatched brine shrimp (BBS) 3 times per day, then eventually microworms and decapsulated brine cysts. Dry food fails for fry; the yolk sac is gone by day 3 and they need something moving to trigger the feeding response. See fry: first 30 days for the full schedule.

Juveniles (4 to 12 weeks) transition from live to crushed pellets around week 6 to 8. Feed four to six times per day in small amounts. This is the growth window; underfeeding here stunts the adult.

The bloat protocol

If the betta refuses food for two days and looks visibly swollen, do this before reaching for medication:

  1. Skip all food for 48 to 72 hours.
  2. On day 4, offer one thawed pea, skin removed, quarter-section. The fibrous interior acts as a mild laxative.
  3. Resume normal feeding day 5.

Nine times out of ten this resolves. The tenth time the fish has pineconing scales and you’re in dropsy territory; see Dropsy.

A two-year-old betta on a varied diet, fed once daily with a fast day, eating in under a minute per meal, rarely has feeding-driven health problems. The rest of the hobby’s feeding folklore (feeding twice a day, feeding flakes as a staple, freeze-dried bloodworms for breakfast) comes from the pet-store bowl era and should die with it.

Frequently asked

How many pellets should I feed?
Four to six 1 to 1.5 mm pellets per day for an adult. Total food volume is roughly the size of the fish's eye. If pellets sit uneaten after 60 seconds, you're overfeeding.
Should I fast my betta?
Yes. One day a week with no food. Bettas are prone to constipation and swim-bladder stress from a full gut, and the intestinal break resets things. Fasting adult bettas is a welfare benefit, not a deprivation.
Is freeze-dried bloodworm a good staple?
No. Freeze-dried lacks moisture, swells in the gut, and is linked to constipation. Use frozen bloodworms instead. Freeze-dried is an occasional treat, not a staple.
Can bettas eat tropical fish flakes?
Not well. Flakes for community tropicals average 30 to 35% protein. Bettas are strict insectivores and need 40% minimum, ideally 45 to 50%, with fish or insect protein listed first.
My betta refuses pellets. What now?
Cold tank, stale food, or the fish is new and stressed. Check heater first. Check ingredient date on the pellet jar (opened pellets go stale in 3 to 4 months). Offer a single frozen bloodworm; a refused bloodworm points at illness, not pickiness.