Meanwhile, the fish will also add extra weight to your home aquarium. This can vary significantly. For example, an Oscar can weigh up to 3.5 pounds, while a small goldfish may only be 0.6 pounds.

The 20-gallon Aqueon Aquarium Starter Kit ($122, originally $147) is one of the best options for new fish owners, especially because it includes a filter, water thermometer, and fish food sample ...