* Fish Size: Different fish species grow to vastly different sizes. A 130-liter tank might be perfect for a few large cichlids, but way too small for a school of smaller tetras.
* Fish Behavior: Some fish are very active and need a lot of space to swim, while others are more sedentary. Aggressive fish require more space to avoid conflict.
* Filtration and Water Changes: The amount of fish you can keep depends on your filtration system and how often you can change the water. Overstocking can lead to poor water quality and health problems.
Instead of a number, here's what you should do:
1. Choose your fish: Research the specific species you're interested in. Look up their adult size, temperament, and recommended tank size.
2. Calculate the "bioload": Bioload refers to the amount of waste a fish produces. Use online calculators or consult with a local aquarium expert to estimate the bioload of your chosen fish.
3. Factor in filtration: Make sure your tank's filtration system is sufficient to handle the bioload of your fish.
4. Plan for water changes: Regular water changes are crucial for maintaining water quality. Be realistic about how often you can do them.
Remember: It's always better to understock than overstock. This gives your fish plenty of space, reduces stress, and makes maintenance easier. Enjoy your aquarium!