Plan an Aquarium

Before you jump in to start keeping your own fish, take a little time to consider the requirements of the aquarium, your wishes for how it should be set up, and how much time and resources you're willing to devote to it. In this article, you'll cover the basics of planning an aquarium and once you've followed the suggestions made here, you'll be reassured that you're making the right choices for long-term healthy and enjoyable fish keeping.


  1. Decide what kind of aquarium you want. Before you even get started on purchasing the aquarium and its supplies, you need to be certain of the type of fish and fish community that you'd like to keep. Some fish will require more work to maintain than others, so this might be one of your first considerations. There are various types of fish tank styles and communities that you can choose from, including a goldfish tank, a cichlid tank, a saltwater tank, aggressive fish, a mixed community, etc. The best choice for a beginner is a goldfish tank or a freshwater tropical community tank as these are the simplest to maintain. Or, you might like to consider a betta (Siamese fighting fish) bowl or tank but, as largely a "fish" tank rather than a "fishes" tank, it's rather limiting.
    • "Community" fish are fish that get along with many other kinds of fish and do not require unusual water conditions. They do not need to be with fish of other species. Most don't need to be with other fish of their own, though some such as tetras, are happiest in schools. But it seems nice to keep at least two fish together so they can't get too bored and it also provides more interest for you.
    • Goldfish are tough, but they do best in cool water. Don't use a heater, and keep them away from a window. They have a fast metabolism and don't digest their food very efficiently, so they produce a lot of waste. A moderately-stocked tank with a good filter is much better than a bowl - and a requirement for a healthy,long life for the fish. The unusual-looking "fancy" varieties do not compete well with the normal-shaped common varieties, so choose one category or the other.
    • Bettas naturally live in swamps in which they can't see very far (and the males, the colorful ones normally sold, defend modest territories by attacking much of what they can see); they can't move very much (and so don't move, eat or excrete much), and often don't have enough oxygen (and so are fortunate to have a special "labyrinth organ" to process gulped air).[1] They do best with clean water and swimming space, so a 2 1/2 gallon (9.46 liter) to 5 gallon tank with a filter is a good way to learn the basics of caring for fish. You can't keep more than one male in a tank (at least not without little in-tank compartments). Female bettas can be kept in groups of 4-6, but make sure one is not very aggressive. They tend to abuse other fish, due to aggression, or be abused, due to ornamental bettas' long, ineffective fins, but can get along with some community fish such as small catfish.
  2. Be prepared to set aside a reasonable amount of money to set up your Aquariums. The greatest cost is when you buy the start-up gear, but there are the ongoing costs of fish food, replacement fish, dechlorinator, etc. Be prepared to spend US$50-$100 for a small tank and equipment (5-10 gallons (19 to 37 liters), freshwater). Saltwater tanks start at hundreds of dollars. However, you might be able to pick up a bargain during sales if you know what you're looking for.
    • If buying or receiving a used tank, check it thoroughly for cracks, hairlines, and any faulty parts. Fill it all the way up in a bathtub or outside to check for leaks. You are best off buying all the electrical equipment brand new even if you get the tank secondhand.
  3. Depending on what kind of aquarium fish content you choose, you need to determine how big the tank will be. If you chose a saltwater tank, you will need at least a 30 gallon (114 liters) aquarium, while the optimal would be a 50 gallon (190 liter) or more tank.[2] The minimum size to try for a freshwater community aquarium would be 20 gallons (75.7 liters). If you decide on a betta, you will need at least a 5 gallon tank (19 liters). Small fancy goldfish should have no less than 20 gallons (75.7 liters) per fish. Large goldfish like comets will need at least a 100 gallon (378.5 liter) tank when full grown. Remember, bigger is always always better when it comes to aquariums.
    • Bear in mind that the surface area is more important than the shape of the aquarium because the surface area is where the gas exchange occurs.[3]
  4. After you have decided what kind of tank you want, decide which (and how many) fish you want. Say you chose a 10 gallon (37 liter) freshwater community aquarium. As a rule of thumb, provide at least one gallon (3.7 liters) of space per inch (2.5cm) of fish. So, in a 10 gallon (37 liter) tank, you could have ten one-inch fishes. For instance, three two-inch (5cm) platies and 4 one-inch neon tetras.
    • The amount of fish flesh, and its metabolism and waste production, increases very roughly with volume, the cube of length. So the inch-per-gallon rule is best with typical little two to four-inch fish. You could add two or three one-inch neon tetras per gallon, but a ten-inch (25.4cm) cichlid might need twenty gallons (75.7 liters) of water to himself and a powerful filter.
    • Make sure your fish can swim several times their body length before turning around. Two five-inch (14cm) fish would be uncomfortable in a little ten gallon tank, but ten of them could swim around merrily in a fifty gallon tank.
    • Sea or marine sourced Fish must be stocked at rate considerably lower than that of their freshwater cousins.[3]
  5. Go to local pet stores or look online for fish that appeal to you and to ascertain their suitability. Then do research on those fish and see if they will be compatible in your tank. Not all fish can be kept in the same tank, even if they are all freshwater community fish (there are different degrees of "community" tolerance), all saltwater fish, or all cichlids (cichlid home environments differ, and each aggressive species' type of aggression differs and should be researched carefully). A tiger barb and a guppy will probably not live together peacefully: tiger barbs will nip long fins.
  6. Decide if you want to plant your tank or not (if it's a freshwater aquarium). Plants can improve water quality and ambiance for fish if healthy, but require more maintenance and equipment such as upgraded lights like those for saltwater reefs (which can create an overheating problem) and some require carbon dioxide injection (good filtration tends to aerate out all the fish themselves produce).[4] If you decide to plant your tank, be careful to choose only plants that will not get too big for your tank. Keep in mind plants are not appropriate for goldfish tanks.
    • If you want to have plants, choose algae eaters that won't eat the plants. Siamese algae eaters ("True algae") are effective and compatible with many other fish.
    • Plastic plants create much of the human-pleasing appearance and most if not all of the fish-pleasing hiding spaces of real plants. You can take them out and wash them to remove excess algae. Soap and other cleaners are very bad for fish, so don't use any or rinse very thoroughly. However, some fish will be much happier with live plants.
    • Saltwater tanks more commonly have corals, most of which photosynthesize, and macroalgae than true plants. Saltwater fish aren't easy to care for, and Take Action to Save Coral Reefs are harder.
  7. Plan the static contents of the tank. Fish need cover. Will you provide it with caves or plants? Fake plants? Real plants? A pirate ship? It is a good idea to sketch your aquarium and lay out where decorations and plants will go. Try to include varied hiding spots and give consideration to the introduction of plants that would best mimic the plants the fish you're getting are used to.
    • Be aware that the decorations and plants suitable for a freshwater tank and for a saltwater tank are extremely different. For starters, you can't grow plants in a saltwater tank because freshwater plants won't grow in saltwater and the plants that will grow in saltwater (macroalgae) provide tasty treats for the fish and disappear in no time![5] And decorations suitable for a freshwater tank may not be suited to a saltwater tank; for saltwater, prefer Clean Plastic Plants, ceramic or plastic ornaments. Do not use driftwood as it will leach Remove a Tannin Stain into a saltwater tank and acidify the water.[6]
    • What sort of gravel, sand, or other substrate will you have for the base of the tank? Even rocks, coral, and substrate must be chosen with care to avoid harming the saltwater balance, so always take these matters into account when selecting the design elements.
  8. Locate the aquarium in a suitable place. There are several considerations here, including safety, temperature, and accessibility.
    • Ensure that the tank sits on a level, solid, and structurally sound surface. Put the tank in a place that isn't likely to get bumped but if it does, it will not topple over. If you live in an earthquake prone region, ask about how you can bolt the tank to the wall or another surface to ensure that it doesn't end up on the ground.
    • Also, check how much weight the floor can take; water can cause a lot of damage. A big tank needs not only to be kept from falling on the floor but supported evenly. With gravel and accessories, a tank weighs about ten pounds (4.5kg) per gallon (3.75 liters). For example, a 55 gallon tank (209 liters) weighs around 600 pounds (274kg) when full of water and the ground needs to be able to cope with the weight.[7] A stand with solid sides rather than just legs is a good idea to help distribute the weight over the entire stand and not just down the four legs.[7] Five gallons (19 liters) can be OK on a sturdy table; ten gallons (37 liters) should, and twenty (75.7 liters) or more essentially must have a purpose-built stand.
    • Ensure that the tank is not located near direct sunlight, drafts, doorways, and windows. You need to guard against temperature extremes and these are the locations likely to cause such variations. Be careful not to locate a tank under a heating or cooling vent either.[7]
    • Keep in mind where you will make water changes when locating the tank; close proximity of a water supply and basin is important.
  9. Keep safety considerations at the forefront. As well as ensuring that the tank is located in a safe and solid position, consider the importance of grounding the tank. Water conducts electricity, and saltwater conducts it very well. Install a ground-fault Determine when to Use Arc Fault Circuit Interrupters (Af Circuit Breakers) outlet (GFCI/GFI) or plug all the equipment into a portable one, which looks like an extension cord with a bulky plug with buttons. Make a "drip loop" with each cord: it should dangle down and come up again before connecting to any socket so water running down it won't get in. Do not plug the aquarium into any outlet that isn't protected by a GFI or into a circuit that isn't protected by a GFI circuit breaker.[7]
  10. Set aside a month or more for your tank to cycle before you get your fish. While you're probably anxious to get your fish to move in, patience is key in this hobby. If you are not going to take the time to set up your tank properly, don't bother. If you put many fish in an "uncycled" tank–one not allowed to develop beneficial bacteria by feeding those depositing themselves from the environment or a bacterial supplement with the waste of a fish or two for a few weeks–you will cause numerous problems with diseases, rising ammonia and nitrate levels, and end up with lots of dead fish. Cycling the tank is about building up the nitrogen content and there is varied advice on how to go about doing this, depending on the tank type. If you ask at the pet store, they may be able to recommend a bacterial culture that you can use (follow the package instructions). Fish author Boruchowitz suggests that caution is your best ally in cycling the tank and for a marine tank, to begin with one to two fish fed sparingly over a few weeks, test the water and if it's within acceptable ammonia limits, to introduce one or two more and do the same for a few weeks more.[8] Then, when it has all regulated after about six weeks, add the entire content of the tank. Another possibility is to use a bio-filter, transferring gravel, a bio-filter wheel, or from an established tank into the new tank.[8] However, it is a good idea to read the suggestions specific to your fish species to find the best way to cycle the tank in your situation.
    • Use this time to learn about tank care and specific requirements. Saltwater tanks, for example, require quite a lot of additional maintenance and equipment, so it's important tor read up on what you should do and to make sure that you have all of the equipment in place, such as a hydrometer, thermometer, how to mix the salt solution, how to vacuum substrate, filtration, lighting, etc. If this list is already wearing you out, it's not a good idea to start with saltwater tanks as a beginner!
  11. Find your fish. When you have set up your tank, cycled it, and settled on what fish you want, you can head to the local fish store and pick out your new aquatic buddies. After that, you might like to read an article on wikiHow for caring for your fish, such as:



  • Invest in a decent tank set up so you won't have to buy additional supplies later. Any problems with a used tank may be readily apparent, but filters and heaters wear out.
  • When buying heaters and filters, go for the best you can afford for a pair. Two smaller heaters are better than one big one. Plan for redundancy in case one breaks.
  • Try to buy fish food in bulk so you can save money and time.
  • Don't rely on general, large style pet store employees for advice on stocking your tank. Ninety percent of the time, they have absolutely no idea what they are talking about. Employees, especially long-term ones, at aquarium-only stores often do though. Still, do your research. Plan for compatible fish that will be fun to watch, occupy different water levels, and be compatible with some kind of animal, whether fish or invertebrate, to eat algae but not plants, if you want to have them.
  • Avoid placing your tank in direct sunlight. This can encourage algae growth and make the temperature of the water hard to regulate.


  • Many retailers will sell you expensive equipment you don't want or need. Research first!
  • GO SLOWLY! One of the most common mistakes beside overstocking a tank is adding too much at once. Be patient and avoid adding more than one or two items at a time.
  • Saltwater tanks are not recommended for beginners as they are very expensive and hard to maintain. Start small and work your way up once you have greater confidence in maintaining an easier type of aquarium.
  • Don't mix fish from different groups. Don't put saltwater and freshwater fish in the same tank: the fish in the wrong kind of water will quickly die. Don't put cichlids and tropical community fish in the same tank: the cichlids may require special water conditions or attack the community fish. Don't put aggressive and community fish in the same tank. Don't mix very small fish and very large fish: the small ones will get eaten.
  • There are normal community type fish and aggressive community type fish. Don't mix them! They are in separate groups for a reason.

Things You'll Need

  • Reputable aquarium retailer
  • Proper lighting
  • Filtration for the amount of livestock in the tank
  • Fish
  • Rocks or other hiding places
  • Heater
  • Thermometer
  • Water test kit

Related Articles

Sources and Citations

  2. D. E. Boruchowitz, Saltwater Aquarium Setup and Care, p. 10, ISBN 0-7938-1043-4
  3. 3.0 3.1 D. E. Boruchowitz, Saltwater Aquarium Setup and Care, p. 11, ISBN 0-7938-1043-4
  5. D. E. Boruchowitz, Saltwater Aquarium Setup and Care, p. 30, ISBN 0-7938-1043-4
  6. D. E. Boruchowitz, Saltwater Aquarium Setup and Care, p. 32, ISBN 0-7938-1043-4
  7. 7.0 7.1 7.2 7.3 D. E. Boruchowitz, Saltwater Aquarium Setup and Care, p. 12, ISBN 0-7938-1043-4
  8. 8.0 8.1 D. E. Boruchowitz, Saltwater Aquarium Setup and Care, p. 34, ISBN 0-7938-1043-4