Aquarium gear guides

How to choose the equipment a beginner's tank needs.

• Best Filter for a 10-Gallon Tank

  How to choose a filter for a 10-gallon aquarium: sponge or hang-on-back, what the tank rating means, flow for small fish, and what else you need to buy.

• Best Filter for Betta Fish: What to Look For

  Choose a filter a betta can live with: why low flow matters, sponge versus hang-on-back, signs the current is too strong, and how to slow it down.

• Best Heater for a 10-Gallon Aquarium

  What size heater a 10-gallon tank needs, why a stuck heater is the real danger, what to look for, and how to keep the tank and yourself safe.

• Best Water Conditioner for Betta Fish

  What a water conditioner must do for a betta: chlorine and chloramine, what ammonia claims really mean, betta-labeled bottles, and dosing small tanks.

• Best Test Kit for a Freshwater Aquarium

  Choose an aquarium test kit: which tests a beginner needs, liquid kits versus strips, why many strips skip ammonia, and when a kit can read falsely high.

• Best Light for a Beginner Planted Tank

  What a first planted aquarium needs from its light: enough brightness for easy plants, a size that covers the tank, adjustable brightness and a timer.

• Best 10-Gallon Fish Tank: What to Look For

  How to choose a 10-gallon fish tank: a bare tank or a kit, the size and weight to plan for, the lid, and what a kit still leaves you to buy.

• Best 20-Gallon Fish Tank: 20 Long or 29?

  How to choose a 20 to 29-gallon fish tank: 20 long, 20 high or 29, the footprint and weight to plan for, and what a kit leaves out.

• Best 40-Gallon Breeder Tank (or a 55)

  How to choose a 40 to 55-gallon fish tank: 40 breeder or 55, footprint and weight, the stand and floor, and what a large kit leaves out.

• Best Filter for a 20 to 29-Gallon Tank

  How to choose a filter for a 20 to 29-gallon aquarium: hang-on-back, sponge or canister, reading tank ratings, flow, media room and upkeep.

• Best Filter for a 40 to 55-Gallon Tank

  How to choose a filter for a 40 to 55-gallon aquarium: large hang-on-back or canister, tank ratings, flow, media, noise and upkeep.

• Best Heater for a 20 to 29-Gallon Tank

  What size heater a 20 to 29-gallon aquarium needs, why maker ratings differ from the rule of thumb, what to look for, and how to stay safe.

• Best Heater for a 40 to 55-Gallon Tank

  What size heater a 40 to 55-gallon aquarium needs, why two heaters are worth considering, what to look for, and how to stay safe.

• Best Aquarium Starter Kit: What to Look For

  How to choose an aquarium starter kit: what it should include, why its tank must fit your species, and which parts are often weak.