Small Saltwater Aquarium Setup Tips

Tropical fish swimming in aquarium outside kitchen

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How small of an aquarium can you have with saltwater? This is asked often, and although you may decide to set up an aquarium less than 40 gallons in size, or what is referred to as mini, micro, nano, and pico tanks, most seasoned aquarists will tell you that the larger the volume of water you are dealing with in an aquarium, the better. The main reason? Because there are fewer concerns with environmental changes occurring rapidly if the water volume is larger.

Small Aquariums Are Unique

With a small volume of water, if a water quality issue pops up, such as elevated ammonia, for example, it can increase quickly, causing disastrous results if is not corrected right away. When you have a large capacity of water, although ammonia may be present, it usually builds gradually and might be thought of as diluted because of the larger amount of water involved. A situation like this can be corrected in a less panicky manner, because it takes a little more time for the problem to reach a critical level.

Tips for the Smaller Saltwater Environment

Smaller is not always easier, or better, and before you decide to put together a small saltwater system, or to buy a mini/nano aquarium kit, here are important keys to success you should know about when setting up and maintaining an aquarium of fewer than 40 gallons in size.

  • You should be patient and diligent.
  • Provide adequate filtration and water circulation. (Example: Don't use an up to 10-gallon capacity hang-on power filter on a 10-gallon tank, but upsize to a 20 or 30-gallon unit.)
  • Incorporating a protein skimmer is a definite plus to remove fast-accumulating and troublesome organic matter.
  • Keep pre-filtering materials clean.
  • To stay on top of what is happening in the aquarium, the water should be tested frequently.
  • Depending on how much bio-load is in an individual system, a regular weekly, bi-monthly to monthly 25 to 50 percent water change is essential for maintaining good water quality, which relates back to the importance of testing the water.
  • Choose tank occupants carefully, and don't overload the system by overstocking.
  • Do not overfeed, especially with foods that can quickly pollute the water.
  • Be cautious about adding buffers, adjusters, trace elements, supplements, other additives, as well as medications. These things can tip the balance of the system very quickly.
  • Monitor the temperature, especially when making water changes. Residual heat from lights, pumps, a skimmer, and other pieces of equipment may cause a water temperature change.
  • Don't overpower the system with too much light. Using the standard 3.5 to 4.0 watts per gallon formula (Example: 10 gallons x 4 = 40 watts), suitable wattage VHO fluorescents, power compact fluorescents, T-5 high output tubes, compact HQI, LED and combination bulb fixtures are good choices. Mini-aquarium kits make lighting easy, because they come equipped with built-in lighting systems. If you plan to keep corals and other zooxanthellae hosting invertebrates, you have to choose the right set up that will support the types of reef animals you plan to keep.
  • To avoid disease problems, which can result in having to treat the aquarium, take the time to quarantine new livestock before placing them in your show tank.

Don't succumb to the pitfall of becoming disappointed and frustrated with aquarium keeping and giving up, because you were ill-prepared. Success primarily stems from being aware of what is expected before starting an aquarium and then making the commitment to follow through with due diligence to take care of it. This especially applies to maintaining a small aquarium.