Everything You Need for Your First Pet Fish
Will’s $20 Tooth Fairy fish turned into a $300 trip to Petco, because it turns out a fish needs a lot of things. This is the list we wish we’d had walking in: the tank we chose, plus the heater, water conditioner, food and other basics a first betta really needs — and the one splurge he talked us into.
Marineland Portrait 5 Gallon Fish Tank Kit
This is the tank we chose for a first betta: five gallons, a filter hidden in the back and a sliding glass lid, in a tall shape that fits on a kid’s dresser. Start here, then add the heater and water conditioner below.
Check price on AmazonA betta is a great first pet for a kid, but the fish is the cheapest thing you will buy. Here is the whole list, roughly in the order you need it: a 5-gallon tank with a filter and a lid, a small heater, because bettas are tropical fish, water conditioner for every fill and every water change, food made for bettas, a test kit so you know the water is safe and a small gravel vacuum for cleaning day. Decorations are optional. In our house, they were not.
One tip before the fish comes home: set the tank up first and let the filter and heater run. A new filter needs time to grow the good bacteria that keep the water safe, so ask at the store about cycling the tank, and use the test kit to check that ammonia and nitrite are at zero. Below the tank we chose, we’ve rounded up everything else on the list.
What else we considered
We also bought
DaToo Mini Aquarium Heater 25W with Thermometer Sticker
Dad says: it’s preset to 78°F, which is right for a betta, so there’s no dial for curious hands to turn. Mom says: it’s tiny, made for 1 to 5-gallon tanks, and comes with a stick-on thermometer.
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We also bought
Seachem Prime Water Conditioner, 250 ml
Mom says: tap water has chlorine that hurts fish, so this goes in with every fill and every water change. Dad says: one capful treats 50 gallons, so a small bottle lasts a 5-gallon tank a very long time.
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We also bought
Hikari Betta Bio-Gold Floating Pellets, 0.7 oz
Mom says: small floating pellets made just for bettas, and one little bag lasts for months. Dad says: a few pellets is a meal; the hardest part is convincing an eight-year-old that more isn’t better.
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We also bought
API Freshwater Master Test Kit
Dad says: it tests pH, ammonia, nitrite and nitrate, so you know the water is safe before the fish comes home and whenever something seems off. Mom says: matching the colors in the little tubes is a good job for a kid with a grown-up.
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We also bought
Aqueon Aquarium Siphon Vacuum Gravel Cleaner Mini
Mom says: a 5-inch gravel vacuum sized for 1 to 5-gallon tanks, with a 6-foot hose and a clip for the bucket. Dad says: pump it up and down to start the water flowing, and it pulls the gunk out of the gravel during a water change.
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We also bought
Penn-Plax SpongeBob Fish Tank Decorations, 3-Piece Set
The one Will talked us into. The kids love: SpongeBob’s pineapple, Squidward’s house and the Krusty Krab, with openings a betta can swim through. Mom says: Cosmo has a whole neighborhood and spends all his time in the Krusty Krab.
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We also bought
CousDUoBe Betta Fish Leaf Pad
Mom says: bettas like to rest near the surface, and this leaf on a suction cup gives them a place to do it. Dad says: it’s the cheapest thing on this list.
Check priceWhy we chose it
Will lost a tooth, the Tooth Fairy left him $20, and he decided to spend it on a betta fish instead of candy or Legos. We went to Petco expecting a small fish and a simple setup. It turns out fish need things: a tank, a filter, water conditioner, food, gravel and, in our case, an entire SpongeBob neighborhood. The $20 adventure ended up at about $300. (The whole story is in our Family Note.)
Nobody had told us what a betta actually needs, so this is the list we would hand a friend before that trip. Start with a 5-gallon tank that has a filter and a lid, add a small heater to keep the water around 78°F, and treat every bucket of tap water with conditioner. After that it is food, a test kit and a gravel vacuum, which together cost less than one fancy decoration.
And then there is the fancy decoration. We bought the SpongeBob set, with SpongeBob’s pineapple, Squidward’s house and the Krusty Krab. Will named the fish Cosmo, and Cosmo spends nearly all his time hiding inside the Krusty Krab. We essentially paid to give a fish his own private fast-food restaurant, and he loves it.
The best part has nothing to do with the gear. Will feeds Cosmo every morning without being asked, and watching him take care of something that depends on him has been worth every dollar. For more on picking the tank itself, our fish tanks for kids guide compares the ones we considered.
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