Freshwater · Beginner
Betta
Betta splendens
Bettas are labyrinth fish that breathe from the surface, but they still need a heated, filtered aquarium, not a vase. A 5-gallon tank is a minimum for a single male.
Min. tank: 5 gal
Care notes →Swimming Fishies.com · aquarium hobby
Cycling, stocking, and species care for home aquariums.
Species profiles, setup guides, and gear notes. Tank sizes match adult fish, not bowls and not the impulse livestock at the store.
Freshwater aquariums
Bettas, tetras, livebearers, cories, and the coldwater truth about goldfish. Start with a cycled, heated tank that matches adult size.
Saltwater aquariums
Clownfish and firefish can work in modest marine tanks. Yellow tangs need room to graze. Same nitrogen cycle, plus salinity.
Featured species
All fish →
Freshwater · Beginner
Neon tetra
Paracheirodon innesi
Keep neon tetras in a school of at least 6, and plan on 8 to 12 in a 20-gallon tank. Adults stay under 1.5 inches. A 10-gallon is the minimum for a small school. Hold the water at 72 to 78°F, soft and slightly acidic (pH 5.5 to 7.0), with plants and dim light.
Min. tank: 10 gal
Care notes →
Freshwater · Intermediate
Goldfish
Carassius auratus
Goldfish are coldwater carp, not bowl ornaments. Fancy strains need tens of gallons and strong filtration; single-tail commons belong in very large tanks or ponds.
Min. tank: 30 gal
Care notes →
Saltwater · Intermediate
Ocellaris clownfish
Amphiprion ocellaris
Ocellaris clownfish are among the more forgiving marine fish, but they still need a cycled saltwater tank, stable salinity, and marine-level testing. A 20-gallon tank can house a pair; 30 gallons is more comfortable.
Min. tank: 20 gal
Care notes →Start here
All guides →Read these in order before you buy fish.
- Step 1: Cycle the tankA fishless cycle usually takes 2 to 6 weeks. Finish it before any fish go in.
- Step 2: Plan your fishEnter your tank size and water type to get conservative groups that link to each species page.
- Step 3: Stocking a 10-gallon tankA 10-gallon fits one plan: a betta, a shrimp colony, or a small school.
- Step 4: Stocking a 20-gallon tankA 20-gallon fits a midwater school plus bottom dwellers on sand, a livebearer group, or a betta.
- Step 5: Size the heaterMost tropical 10-gallon tanks want about 50W, and most 20-gallon tanks want about 100W.
- Step 6: Feed small amountsMost community fish need a pinch they finish in about two minutes, once or twice a day.
Latest
The six newest pages on the site, across fish, guides, and gear.
Gear
Aquarium light timer
Start a new tank at 6 to 8 hours of light a day and let a timer run it, so the schedule doesn't depend on you remembering. Check whether your light already has a timer built in before you buy one. Then pick a mechanical outlet timer, a digital one, or a smart plug.
See notes →
husbandry
How to get rid of pest snails
Bladder, ramshorn, and Malaysian trumpet snails come in on plants and multiply on leftover food. Feed less first, then trap them overnight and pick them off by hand. Assassin snails help over a few months. Copper snail killers also kill shrimp and the snails you wanted.
Read guide →
Freshwater · Beginner
Dwarf gourami
Trichogaster lalius
Dwarf gouramis (Trichogaster lalius) grow to about 3 to 3.5 inches and are the most common gourami in shops. One male fits a cycled 10-gallon, and a 20 gives him room for a school or two females. Keep them at 75 to 80°F with floating plants and gentle flow. Farmed fish often carry dwarf gourami iridovirus, so buy carefully and quarantine.
Min. tank: 10 gal
Care notes →
stocking
Stocking a 55-gallon tank
A 55 is 48 inches long, about 13 inches front to back, and 21 inches tall. That height suits angelfish and the length suits fast swimmers, but the narrow floor leaves less room for fish that hold territory. Three plans that pass the calculator, with fish counts, filter and heater sizes.
Read guide →
Gear
Ich medication and aquarium salt
For white spot in a freshwater tank, buy one ich medication and dose it from the label for your real gallons. Hikari Ich-X and API Liquid Super Ick Cure are the two bottles we reach for. Aquarium salt is an optional extra for hardy fish in a tank without plants, shrimp, or snails.
See notes →
stocking
Endler vs guppy
A male Endler is about an inch long, with a slim body, a short tail, and often a black bar or spot in the middle of the flank. A male guppy is half again as big and usually carries a much larger tail. Both want the same hard, warm water, and they crossbreed, so keep them in separate tanks if you want pure fish of either kind.
Read guide →What fits this tank?
A conservative stocking calculator. Tank gallons, freshwater or saltwater, and your experience, then ideas that link to real species pages. Not inch-per-gallon.
Gear, with the fine print
Starter kits and test kits, written as buying notes rather than fake rankings. Shopping links may earn a commission.