Long tanks
Often better for active swimmers and species that use horizontal space.
Aquarium basics
Choosing an Aquarium
The best aquarium is not necessarily the biggest one you can buy, and it is definitely not always the smallest one you can fit on a shelf. A good choice starts with the animals you want to keep, the space available, and how much maintenance you can realistically do.
Start with livestock
Choose the animals before choosing the tank.
It is much easier to choose a suitable aquarium once you know what will live in it. Adult size, behaviour, swimming style, group size, waste production and water requirements all affect the amount of space and equipment needed.
Plan for adult animals, not the size they are in the shop.
A juvenile fish that looks tiny today may need far more swimming
room later. The tank should suit the animal's long-term needs.
Tank size
Small tanks are usually less forgiving.
Smaller aquariums contain less water, which means temperature and water chemistry can change more quickly. A small amount of excess food or waste also has a larger effect in a small volume of water.
Larger aquariums are not automatically easy, but they usually give you more room for stable water conditions, proper filtration and natural behaviour.
“Small tank = beginner tank” is a bad shortcut.
Tiny aquariums often require more careful maintenance, not less.
Shape
Litres do not tell the whole story.
Two aquariums can hold a similar volume of water but provide very different usable space. Long tanks provide more horizontal swimming room. Tall tanks provide more vertical space but can be awkward for surface-breathing fish or maintenance.
Tall tanks
Can work well for certain displays, but height does not replace swimming length.
Wide tanks
Useful for aquascaping, bottom-dwelling species and giving territorial animals more floor space.
Bowls & unusual shapes
Often look attractive but may be awkward to filter, heat, cover and maintain properly.
Placement
Think about where the aquarium will actually live.
An aquarium is heavy once filled. Water, glass, substrate, hardscape and equipment add up quickly, so the stand must be suitable and level.
- Avoid unstable furniture.
- Keep the aquarium away from places where it can be knocked.
- Leave enough space behind and above the tank for cables and maintenance.
- Avoid strong direct sunlight if possible, as it can contribute to overheating and algae.
- Make sure there is convenient access to power and water.
Filtration
Pick a filter that suits the livestock, not just the tank volume.
Filtration provides mechanical cleaning and, more importantly, space for beneficial microorganisms to live. Flow rate should suit the animals being kept.
A strong filter is not automatically a better filter. Bettas and some shrimp setups benefit from gentle flow, while larger or more active fish may need more circulation.
Sponge filters
Gentle, simple and excellent for shrimp, fry and breeding tanks.
Internal filters
Compact and easy to install, though they take up space inside the aquarium.
Hang-on-back filters
Useful for many small and medium tanks while keeping most filter media outside the display.
Canister filters
Offer large media capacity and are common on bigger or more heavily stocked aquariums.
Heating
Temperature should match the species.
Tropical species often need a heater unless the room itself stays consistently warm enough. Choose a reliable heater appropriate for the aquarium volume and always check the actual water temperature with a thermometer.
Shrimp, plants and some fish can tolerate cooler conditions, while species such as Betta splendens require consistently warm water.
Lid & surface access
A lid solves more problems than people expect.
Fish can jump, shrimp can climb, and evaporation can be surprisingly high. A lid can reduce water loss and keep animals inside the tank.
Species that breathe atmospheric air still need easy surface access, so floating plants should not completely cover the surface.
Maintenance access
If maintenance is annoying, it will probably happen less often.
Make sure you can comfortably remove the lid, reach the filter, clean the glass and siphon the substrate. A beautiful setup becomes frustrating quickly if every water change requires moving half the room.
Think about where buckets, hoses, nets and test kits will be used before the tank is filled.
Equipment
Buy what solves a real need.
- A suitable filter.
- A heater if the livestock needs one.
- A thermometer.
- Water conditioner for chlorinated tap water.
- A reliable water test method.
- A light suitable for the plants you intend to grow.
- A lid if the species or room conditions make one useful.
You do not need every aquarium gadget on day one.
Spend money on the equipment that affects animal welfare and water
stability first.
Common mistakes
Things worth avoiding from the start.
- Buying a tank first and choosing livestock afterwards.
- Assuming a small aquarium will be cheaper and easier to maintain.
- Using furniture that was never designed to hold an aquarium's weight.
- Choosing a filter that creates excessive current for the species.
- Leaving no room around the aquarium for maintenance.
- Stocking based on juvenile fish size.
- Adding livestock before the aquarium is cycled.
A simple order
Plan the tank in this sequence.
- Decide which animal or group of animals you genuinely want to keep.
- Research their adult size, social needs, temperature and behaviour.
- Choose an aquarium that gives them suitable long-term space.
- Select filtration, heating and lighting based on that setup.
- Choose a safe location and stand.
- Set the aquarium up and cycle it before adding livestock.
Keep reading