What Fish Are Good for a 10 Gallon Tank Guide: 12 Picks
The best fish for a 10-gallon (38 L) tank are small, peaceful nano species that stay under 5 cm and produce a low bioload. A single betta, a chilli rasbora school, sparkling gouramis or a pygmy corydoras shoal all thrive at this volume, while goldfish, angelfish and most barbs do not. The phrase fish good for 10 gallon tank attracts beginners who often inherit a starter kit and need realistic stocking advice rather than aspirational lists. This FAQ from Gensou Aquascaping at 5 Everton Park covers 12 species that genuinely belong in a 10-gallon (38 L), with notes on what works in Singapore tap water at 28-30°C.
Why 10 Gallons Limits Your Choices
Thirty-eight litres sounds generous until you factor in substrate, hardscape and plants — usable swimming volume drops to 28-30 L. Surface area is also limited, which caps oxygen exchange. The fish that suit this footprint share three traits: small adult size under 5 cm, peaceful temperament, and tolerance of slight nitrate accumulation between weekly water changes. Anything that grows past 6 cm, schools in groups of more than ten, or actively defends territory will outgrow the volume within months.
Betta Splendens — The Classic Single Fish
One male Betta splendens in a planted 10-gallon (38 L) is the cleanest match. The fish gets vertical swimming space, hides in floating plants, and never crowds the volume. Pair with three or four shrimp from the shrimp range if temperament allows, and skip the cohabitation experiments with guppies that always end badly.
Chilli Rasbora — Nano Schoolers
A school of 10-12 chilli rasboras (Boraras brigittae) at 1.5 cm each is one of the most colourful uses of 38 L. They thrive in soft, slightly tannin-stained water and sit happily at PUB tap parameters. Local availability is steady at C328 and Iwarna at SGD 1.50-2.50 per piece. They share well with shrimp and snails.
Pygmy Corydoras — Bottom Patrol
Six to eight Corydoras pygmaeus or C. hastatus work where a full-size cory school does not. They reach 2.5-3 cm, occupy the bottom third, and tolerate the same 25-28°C range as most nano species. Sand substrate from decoration and substrate protects their barbels — gravel does not.
Sparkling Gourami — Voiced and Tiny
The sparkling gourami (Trichopsis pumila) tops out at 4 cm and audibly clicks during courtship. A trio of one male and two females fits comfortably with mid-water dither fish. They are an unconventional but realistic pick that beats the more famous pearl gourami, which grows too large for this volume.
Endler Livebearers — Colourful and Small
Pure-strain Endler’s livebearers (Poecilia wingei) reach 3-4 cm in males. A trio of all-male Endlers from livebearers avoids the population explosion mixed-sex groups produce in a 10-gallon (38 L). Avoid hybrid guppy-Endler crosses — they grow larger.
Celestial Pearl Danio — Galaxy Rasbora
A school of 8-10 celestial pearl danios (Celestichthys margaritatus) at 2.5 cm each suits a planted 10-gallon (38 L) with subdued lighting. They prefer slightly cooler water at 22-25°C, so consider an aircon room or a small cooling fan to keep summer highs in range.
White Cloud Mountain Minnow — Cool-Water Pick
White clouds (Tanichthys albonubes) tolerate 18-26°C and skip the heater entirely in air-conditioned bedrooms. A school of 8 stays peaceful and active. They are widely sold at C328 and on Carousell at SGD 2-3 per piece and remain an underrated choice for new keepers.
Scarlet Badis — The Micro Predator
One male and two female scarlet badis (Dario dario) make an unconventional but excellent 10-gallon (38 L) display. Males flare crimson with cyan bars; females stay tan. They eat live or frozen feed only — pellet refusers — so factor in live and dried feed from the freezer.
Ember Tetra — Glowing Schoolers
A group of 10-12 ember tetras (Hyphessobrycon amandae) at 2 cm each glows orange against dark substrate. Singapore tap water suits them with a small dose of water conditioner to neutralise chloramine. They tolerate community life with bettas, shrimp and snails.
Otocinclus and Amano Shrimp — Cleanup Crew
Three otocinclus catfish and four Caridina multidentata Amano shrimp form an unobtrusive cleanup crew. Otos need an established tank with biofilm — add them after six to eight weeks. They handle most of the algae a snail would, while Amanos demolish hair algae the otos miss.
What to Skip in a 10-Gallon
Goldfish, angelfish, common plecos, oscars, tiger barbs, dwarf cichlids and any fish over 6 cm adult size should not enter a 10-gallon (38 L). Pet-shop staff sometimes sell them as ‘starter fish’ but every one of these outgrows the volume within a year. Choose from the 12 picks above and you sidestep the rehoming problem.
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
