How All-in-One Aquariums Work

Tropical Aquarium.
Aquariums are both beautiful and relaxing. See more pictures of aquarium fish.
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An aquarium can be a beautiful addition to your home. Not only are they relaxing to look at, your friends will ooh and aah at the colorful fish and vibrant underwater plant life inside. Even the sound of water trickling through the filter return is soothing. If you're not convinced yet, keep in mind that aquariums also can serve as excellent educational tools for children.

For all the wonderful things that aquariums are, there's one thing that an aquarium isn't: simple. Inside a typical aquarium is a miniature ecosystem with many variables and elements that have to work in concert and stay in balance. If things move away from that healthy balance, your fish will get sick and eventually die. Proper filtration, cleaning, the correct kinds of fish, lighting, heaters, cleaning, currents, oxygenation, ph balance and salt concentration are all crucial factors that contribute to the livelihood of your aquarium.


For the beginning aquarist, maintaining this precarious balance can be overwhelming. The research involved in figuring out what size aquarium to get, what fish to put in it, which filters to use with a given volume of water and all the other factors crucial to building a successful aquarium is pretty daunting. There are entire books on the subject of aquarium lighting alone.

While maintaining a healthy aquarium full of fish will always take a lot of hard work and experience -- in fact, most aquarists will tell you that's part of the appeal -- there's one way to take some of the guesswork out of purchasing an aquarium set-up. All-in-one aquariums are kits that provide all the basic tools needed to get an aquarium up and running. The hood, lights and filters are designed specifically to fit the kit's provided tank. In addition, the tank and stand are constructed for ease of use.

Is an all-in-one aquarium the right kind of aquarium for you? This article will help you find out.



All-in-One Aquarium Combinations

An all-in-one aquarium is a ready-made kit in which all the elements of the aquarium are designed to fit and work together. For example, the hood that contains the lights fits perfectly onto the top of the tank and has a space for the filter mechanism. The filter is designed to have an appropriate capacity for the amount of water in the tank. The kit also includes a heater, thermometer and substrate (the gravelly material that covers the aquarium's floor).

Some all-in-one aquariums might include extras like a stand suited for the size and weight of the tank. The various electronic components might be integrated by a single power supply, so you just have to plug one cord into the wall to power the filter, heater and lights. Some all-in-ones have an integrated power strip, so you can plug in other devices like powerheads or additional heaters and still use the single wall plug.


At the top end of the all-in-one aquarium spectrum are so-called nano-reefs, or aquariums designed to create a living coral reef in a tank. They usually include water conditioners, salt and salt mixing equipment, testing kits and the reef base, a calcium carbonate substrate that gives various saltwater species places to live and hide.

All-in-one aquariums range from small kits of 10 gallons (38 liters) or so made in designer shapes and colors to large reef systems of 60 gallons (227 liters) or more. They come with affordable, yet heavy glass tanks or lighter, more expensive acrylic tanks. The number of combinations is huge, with lots of choices suitable for novice and experienced aquarists alike. You can find all-in-one aquariums at almost any specialty fish store.

Next, we'll look at the pros and cons of all-in-one aquariums.


Pros and Cons of All-in-One Aquariums

There are several advantages and disadvantages of all-one-aquariums.

The pros include:


  • Easy set-up: If you're a beginner, an all-in-one aquarium helps you avoid having to match filter capacity to tank size and all the other small technical hurdles that can plague a first aquarium. The entire kit has been designed to work together. Even expert aquarists can appreciate getting all the pieces in one package when setting up a new aquarium.
  • Hand-holding for the beginner: Since all-in-one aquariums appeal to newbies, they usually include extra information on set-up, fish selection and care, and aquarium maintenance. Sure, you could buy a book on aquariums, but if you're buying a saltwater aquarium of a certain size, it's nice when the manufacturer recommends specific species and numbers of fish that would do well in that particular type of aquarium.
  • Easier maintenance: Keeping an aquarium clean and healthy requires a regular maintenance schedule -- no matter what kind of aquarium it is. However, all-in-one aquariums are often designed with easy maintenance in mind. Filter cartridges are placed so they are easy to access and change or clean. The hood is designed to lift without interfering with the lights or filter. These things are possible without an all-in-one system, but often when you've bought all the parts separately, they don't work together quite as smoothly.
  • Aesthetic appeal: Aquariums look wonderful, but an all-in-one tends to have a more unified design that can fit the décor of a room better than a glass tank with a basic hood might. All-in-ones can be designed to hide the mechanical and electronic components from view.

Cons include:

  • Inadequate equipment: When you buy an all-in-one aquarium, you're trusting the manufacturer to have the appropriate heater, filtration and lighting for a given tank. They don't always get it right, though -- sometimes, inadequate filters are used to keep costs down. Insufficient lighting is another common problem, especially with reef systems.
  • Difficulty of use: Retailers and manufacturers of all-in-one aquariums tout them as "plug and play" aquariums. This isn't really true -- you can't just add fish and water and have a successful aquarium. There's still a lot of work and expertise involved, don't think that using an all-in-one will be easier than it actually is.
  • Hard to expand or adapt: If you're using basic glass tank for your aquarium, it's relatively simple to change your lighting set-up or add additional heaters. You can add more powerheads to generate currents and keep water flowing to stationary plants and anemones. Ironically, however, an all-in-one aquarium is somewhat restricted by its design. It was built for use with one particular filter or light, and using a different one or adding more might be impossible.
  • Cost: Typically, an all-in-one aquarium costs more than a comparable aquarium built from separate parts. You pay a premium for having much of the work done for you.


Lots More Information

Related HowStuffWorks Articles

Related HowStuffWorks Articles


  • Cunningham, John. "What Is The Best Salinity To Keep A Saltwater Aquarium At?" Aquarists Online. March19, 2009. Accessed Dec. 23, 2009.
  • Cunningham, John. "Which Is Better - An Acrylic or Glass Aquarium?" Aquarists Online, March 19, 2009. Accessed Dec. 28, 2009.
  • Paletta,Michael S. The New Marine Aquarium: Step-By-Step Setup & Stocking Guide. TFH Publications, May 1999.
  • Sprung, Julian. The Reef Aquarium: A Comprehensive Guide to the Identification and Care of Tropical Marine Invertebrates. Ricordea Publishing, July 1994.