Nano Tanks

Child admiring nano fish tank


Nano tanks are rapidly growing in popularity due to their petite size, compact setup, and aesthetic designs. While most often used for saltwater or marine aquariums, nano tanks are also fantastic options for freshwater aquariums.

Technically considered to be 10 gallons or less, the term “nano” is also used to describe small tanks under 30 gallons. Continual advancements in aquarium technology have created a wide variety of nano tanks on the market that are beautifully and creatively designed, and there’s one for just about any place you can think of putting one! 

How Do Nano Tanks Work?

Nano tanks are a compact setup that includes lighting and multi-level filtration all in one. While conveniently sized, nano tanks actually make caring for its inhabitants more challenging due to the small volume of water. The less water, the more extreme the effects of fluctuations in water chemistry and temperature.

Dwarf Rainbow TetrasThis is especially true for saltwater aquariums, where the balance of the ecosystem is very easily thrown off. A small spike in ammonia in a tank larger than 30 gallons may not be noticeable thanks to the large volume of water, but a spike in a nano tank could be enough to harm or kill your fish.

Setting up your nano tank

Healthy aquariums are a delicate balance of bacteria and chemistry that enable an ecosystem in which your fish can live and thrive. This balance can’t be achieved immediately--the tank will need to go through a period of “cycling” before you can safely begin to introduce fish.

Filtration is required for a successful aquarium and, for optimal results, should be incorporated both mechanically and naturally. Mechanical filtration is done through a filtration system that should already be built into your nano tank. Natural filtration includes using live plants, sand, or “live” rock to create an equilibrium that contributes to this balance.

Cycling and filtration vary somewhat from freshwater to saltwater aquariums. Incorporating natural filtration into freshwater aquariums is optional and includes adding live plants and eco-complete gravel instead of artificial plants and standard gravel. If you’re interested in freshwater, here’s a quick guide to setting up your tank.

Saltwater aquariums, on the other hand, require natural filtration through “live” rock and sand. Cycling your saltwater tank is slightly more complex than cycling a freshwater tank, so if you’re interested in saltwater, here’s an in-depth guide to cycling.

What you’ll need

Aside from a quality nano tank with a built-in pump, lighting, and filtration, you’ll need the following items:

Additional items for a saltwater tank:

  • Live rock and sand
  • Filtered salt water
  • Salinity refractometer
  • Protein skimmer (some nano tanks have one built in)

Maintaining your nano tank

Because fluctuations in a nano tank’s chemistry and temperature are more detrimental, daily water quality and temperature checks are necessary. Test strips are the quick and easy way to test your parameters every day, but if you notice something is off, it’s best to use a more advanced test kit to get to the source of the problem.

African Dwarf Frog

Dangerous fluctuations will affect your fish, causing them to hide, discolor, or gasp for air. Don’t wait until your fish are affected to take proper care of your tank! When one thing goes wrong in a nano tank, it can cause the whole system to crash within hours, killing all of your fish and causing you to start over from scratch. Take daily, preemptive steps to avoid these fluctuations from occurring in the first place.

Colorful Halfmoon Beta Fish

One way you can avoid problems in through weekly partial water changes of 10-20% of your water volume. In nature, natural water flow and currents constantly bring in fresh new water, so in the case of your nano tank, you have to be the one to frequently introduce new water.

Another way you can avoid fluctuations is by keeping the bio-load low, meaning less fish, as their poop contributes to the amount of decaying matter in the tank.

And be sure to change the filter or filter media as often as the instructions indicate.

Last but not least

After you’re all set up and finished with the 4-6 week cycling process, it’s time to pick out your new nano tank’s inhabitants! There’s a whole array of colorful and fascinating fish, plants, invertebrates, and corals to choose from.

Keep in mind that if you choose a nano tank over a larger tank, you’re also choosing to keep your inhabitants sparse. Only a couple of fish that are small when full-sized can be kept happily and comfortably in a nano tank; small clownfish are a favorite for saltwater nano aquarists.

However, you can make up for the small number of fish with a breathtaking variety of corals (for saltwater) and plants (for freshwater).

Have fun setting up your new tank, and drop by Pets on Broadway to talk to one of our aquarium specialists about any questions or concerns you may have!