* Fish size: A 20-gallon tank could hold a few large goldfish or a lot of tiny neon tetras.
* Fish species: Different fish have different needs for space, water conditions, and social behavior. Some fish need more room to swim, while others are fine in smaller spaces.
* Filtration: A well-filtered tank can support more fish than one with inadequate filtration.
* Tank layout: A tank with lots of plants and hiding places can often support more fish than a bare-bottom tank.
General Rule of Thumb:
The "one-inch-per-gallon" rule is a common starting point, but it's often too simplified. It's best to do more specific research based on the fish you're interested in.
Instead of focusing on a number, consider these factors:
* Research specific fish: Find out the adult size, social behavior, and water parameters of any fish you're interested in.
* Choose compatible fish: Make sure the fish you choose are compatible in terms of size, temperament, and water needs.
* Overstock cautiously: It's better to start with fewer fish and gradually add more as you learn about your tank's capacity.
* Monitor your tank: Pay attention to water quality, fish behavior, and signs of stress.
It's always better to understock a tank than to overstock it. This will help you maintain a healthy and happy environment for your fish.