16/10/2026
WE GET ASKED THIS EVERY WEEK!
💬 “How many fish can I put in my tank?”
The answer isn't simply a number based on tank size.
When determining an appropriate stocking level, several factors need to be considered:
💧 Aquarium volume and dimensions: Available swimming space and territory.
🐟 Species and adult size: Fish should be stocked according to their adult requirements, not their size at the time of purchase.
⚙️ Filtration and biological capacity: Your aquarium must be able to process the waste produced by its inhabitants.
🤝 Compatibility and behaviour: Temperament, social requirements and territorial needs all influence stocking decisions.
🧪 Water quality and maintenance: Regular testing and appropriate maintenance help ensure a healthy, stable environment.
Overstocking can increase stress, compromise water quality and contribute to health problems. A properly stocked aquarium prioritises the long-term health and welfare of its inhabitants.
Our advice: Plan your stocking around the needs of the fish, rather than trying to fill every available space. And remember, just because there's room for more fish doesn't always mean your tank is ready for them!
Need help deciding what your aquarium can comfortably support? Visit us in-store and speak with our team.
👇 Comment with your tank size and the species you keep, and let's talk stocking!
Open every day 10am -6pm
📍 232-236 Bell St, Coburg VIC
🛒 www.coburgaquarium.com.au
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