Fish

The filter is the most important piece of equipment on your aquarium. A good heater keeps the water warm. A good light grows plants. But the filter is what keeps fish alive. Without adequate biological filtration, ammonia builds up, fish get stressed, and you end up with sick or dead fish no matter how careful you are with feeding and water changes. We tested 6 aquarium filters across three main types — hang-on-back (HOB), canister, and sponge — in tanks ranging from 5 to 75 gallons. We ran each filter for at least 4 weeks, measured flow rates, noise levels, ease of cleaning, and how well each one maintained ammonia and nitrite at zero in a stocked tank. ...

The first aquarium is a strange purchase. You’re buying a glass box that you’ll fill with water, plug into the wall, and spend the next few years staring at while strange floating creatures drift past. It’s weirder than it sounds — but there’s something about a well-maintained tank that a screensaver or a fireplace video can’t touch. The trick is picking the right tank for your first setup. Too small and the water chemistry swings wildly (small tanks are harder, not easier). Too large and the upfront cost and maintenance scare you off. A good starter kit removes most of the guesswork: filter, light, heater, lid all included. You just add water, gravel, and fish. ...