Tank Buster Fish - Think Carefully Before Buying One!

What is a tank buster fish?

Tank Busters, also known as Monster Fish, are fish that get BIG; too big for the average hobbyist's store-bought aquarium. Opinions vary as to what constitutes a Tank Buster fish, but for this article, we're referring to any fish that has the potential to grow over 12 inches. They can be hard to resist when they're 3 or 4 inches long, which is the size normally offered in stores, but they quickly outgrow their homes. As many hobbyists soon learn, sometimes their tank mates begin to disappear, as well!

Here are just a few Tank Buster species that are offered in aquarium stores:

  • Pacu
  • Clown Knife
  • Irridescent Shark
  • Chinese Hi Fin Shark
  • Tiger Shovelnose
  • Catfish Sturgeon
  • Redtail Catfish
  • Six-Banded Distichodus
  • Giant Gourami
  • Alligator Gar
  • Peacock Bass
  • Tiger Datnoid
  • Silver Arowana
  • Jaguar Cichlid (Parachromis managuensis)
  • Common Plecostomus
  • Oscar
  • Columbian Shark Catfish
  • Tinfoil Barb
  • Koi
  • Flagtail Prochilodus

Do fish grow to their tank size?

Some aquarists fall into the trap of "it will only grow to the size of my aquarium." This is false – tank size does not govern how large a fish will get. This myth is the cause of many unwanted, stunted fish in poor health, as well as a fair number of stressed out fish owners. Another consideration is that most Tank Buster species live well over 20 years, making them a long-term commitment for anyone who purchases them.

Ethical concerns with purchasing tank buster fish:

We all want the best for our pets, and fish should be no different. All aquarium fish deserve the best living conditions possible. Our inability to do so harms the fish we keep and gives the aquarium hobby a bad reputation. This, in turn, could lead to increased regulation of the aquarium industry, with the potential to close it down altogether. Purchasing Tank Buster fish helps perpetuate demand for them, creating a continued supply. Some aquarists have resorted to releasing unwanted fish into the wild, which is not only illegal, but extremely detrimental to native species and the environment.

Husbandry challenges:

Space is the first thing anyone who considers owning Tank Buster fish must plan for. You'll need a minimum of 500 to 1,000 gallons to properly house most Tank Buster fish. A 150 or 210 gallon seems enormous to us, but to a fish that might have spent its life in the Amazon River or an average size lake, it's cramped quarters. To put things in perspective, imagine spending the rest of your life in an average-size home bathroom, never being allowed to leave. Many large fish like to move things around in their habitat. Decorations should be robust and securely placed to avoid the risk of them damaging the tank and equipment or injuring the fish if they're knocked over.

Next thing to consider is water quality. You'll need a filtration system capable of processing the large amount of waste produced by fish this size. Keeping large fish is a lot more work than the average tropical fish, so ask yourself, will you be able to keep up with water changes, tank and filter maintenance, the cost of food, filter media and other supplies? Also, don't forget the electrical expense of operating an extra-large aquarium.

Big fish eat a lot, and some Tank Buster species have specialized diets. Will you be able to provide the proper conditions and diet for 20 years or more? Finally, there are a limited number of compatible tank mates for truly large fish and more fish means you'll need even more space and filtration.

What if I have a tank buster fish I can no longer take care of?

First, if you find you can no longer keep a fish or other pet, NEVER release it into the environment! It is illegal in most places, and the results can be catastrophic to native species and the ecosystem. Public aquariums and zoos usually cannot accommodate them either.

Your local aquarium store may be able to help, but they are not obligated to accept or offer anything for them, even if you bought them there. Always call first to make sure they are willing to accept your fish before bringing them in. Your local aquarium society may have members that have the expertise and space to take in oversized fish. You can also check for large fish rescues or re-homing services online.

Where can I find out how big a fish gets?

Here are some sources of information about how large a fish will get:

Why banning tank buster fish is not an option:

Banning the sale of large fish from the aquarium hobby might seem like an effective solution, but it may have undesirable consequences and could even have the opposite effect. A total ban would almost certainly create a black market. Because many Tank Buster fish are collected in the wild, their care and treatment during capture and shipping would likely be compromised. In addition, those who engage in illegal collecting practices may have less concern for the environment than legitimate collectors, resulting in damage to natural habitats of target species and other animals. A ban may also open the door to further restrictive regulation of the aquarium industry.

The best solution is for hobbyists to not purchase these fish. The reason stores stock these fish and importers and wholesalers continue to supply them, is that people continue to buy them. There are plenty of other fish that are interesting to keep and make far better long-term pets.

Responsible Ownership

Always research fish before making a purchase to be sure you can provide proper care for their entire life. Deciding to purchase a Tank Buster fish is a major commitment. Sometimes life throws us curve balls and our best intentions are thwarted. Unexpected events are part of life; poor planning for special needs pets is not.

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