Equipment thatkeeps thetank thriving.
Buying guides for aquarium filters, heaters, lighting, skimmers, test kits and aquascaping gear, sized to your tank's gallons and matched to the fish, plants and corals you keep.
Equip by system
Tank, filtration, heat and flow, light and water testing. Size each to the tank first.
Set it up right
- 01
Aquarium Filter Types and Sizing: Canister, HOB, Sponge and Sump
Hang-on-back filters are simple and good for small to mid tanks; canister filters hold more media and stay quiet under the stand for larger tanks; sponge filters are gentle and cheap for fry, shrimp and quarantine; sumps give the most capacity for big and reef systems.
- 02
Aquarium Heater Size Guide: Watts per Gallon and Controllers
A common starting point is about 3 to 5 watts per gallon, using the higher end when the room is much cooler than the target water temperature.
- 03
The Aquarium Nitrogen Cycle: How to Cycle a New Tank
Before adding fish, a new aquarium needs a colony of beneficial bacteria that turns toxic ammonia into nitrite and then into less harmful nitrate.
- 04
Aquascaping Basics: Substrate, Hardscape and CO2
Aquascapes start with substrate and hardscape.
- 05
Freshwater vs Saltwater Aquarium: Startup and Running Costs
Freshwater tanks cost less to set up and run, need simpler equipment and are more forgiving for beginners.
- 06
Planted Aquarium Lighting: PAR, Spectrum and Photoperiod
Choose a planted tank light by PAR (photosynthetically active radiation) at the substrate, not watts.
- 07
Reef Tank Water Parameters: Salinity, Alkalinity, Calcium and More
Reef tanks thrive on stable water.
Aquarium Equipment questions, answered
What size filter do I need for my aquarium?
Many keepers aim for 4 to 6 tank volumes per hour of rated flow for freshwater, more for heavily stocked tanks.
Read: Aquarium Filter Types and Sizing →What size heater do I need for a 20 gallon tank?
About 75 to 100 watts in most rooms, more if the room is very cold.
Read: Aquarium Heater Size Guide →How long does it take to cycle an aquarium?
Often four to eight weeks, sometimes faster with bottled bacteria or media from an established tank.
Read: The Aquarium Nitrogen Cycle →What substrate is best for planted tanks?
Aqua soils give the most nutrients for rooted plants. Inert substrates work with root tabs and easier plants.
Read: Aquascaping Basics →Is a saltwater aquarium harder than freshwater?
It needs more equipment and closer attention to water chemistry, especially for reef tanks. Many beginners start with freshwater.
Read: Freshwater vs Saltwater Aquarium →How much light do aquarium plants need?
Low-light plants do well around 15 to 30 PAR at the substrate; demanding plants need 50 or more plus CO2.
Read: Planted Aquarium Lighting →Animal welfare comes first
Every recommendation is sized to tank volume and the needs of the livestock.
Each guide says who the equipment suits, who should look elsewhere, and what to check before you buy.
Brands cannot buy a review or a spot on a list. Partner codes save you money; they never decide what we recommend.
Prices are dated, codes are updated across the site at once, and pages are revised when a product, standard or rule changes.
The aquarium equipment index
- 01Tanks & filtrationNano to large tanks, stands, canister, hang-on-back, sponge and sump filtration.2 pages
- 02Heat, light & flowHeaters and controllers, chillers, planted and reef LED lighting, pumps and wavemakers.2 pages
- 03Water & testingFreshwater and reef test kits, conditioners, RO water, salt mixes and refractometers.1 page
- 04Reef systemsProtein skimmers, dosing pumps, reactors, auto top-off and controllers.1 page
- 05Aquascaping & careSubstrates, hardscape, CO2 systems, tools, automatic feeders and maintenance gear.1 page
- 06Breeding & quarantineQuarantine and hospital tanks, breeding setups, livestock transport and battery backups for outages.0 pages