Freshwater Equipment
Filters, LED lights, heaters, CO2 systems, pumps and reverse osmosis for aquariums.
Advice and care
How to choose aquarium equipment
The basic kit is a filter, a light and a heater; the rest depends on plants and livestock.
Filter by volume
Choose a filter whose rated litre range covers your tank's volume.
Light for plants
Match the light's length to the tank and its power to how demanding the plants are.
Steady warmth
Tropical fish need a heater that keeps the water steady at 24–26 °C.
Popular brands
All brandsFrequently asked questions
Is an external filter better than an internal one?
An external filter holds more media and takes no space in the tank, so it suits larger and planted tanks. In a small tank or for shrimp, an internal or sponge filter is enough.
When do I need reverse osmosis?
When tap water is hard but you keep shrimp or fish that need soft water, and for mixing salt water for a marine tank.
Read more
Aquarium equipment keeps the water clean, warm and well oxygenated and gives plants enough light. A filter pushes water through sponges and ceramics where beneficial bacteria live and turn fish waste into less harmful compounds. A heater's thermostat switches heating on and off as needed and keeps the temperature steady even when the room cools down.
In a planted tank it is worth adding a CO2 system and stronger lighting: plants grow faster and algae find it harder to compete. An air pump helps when there are many fish or little water movement. A reverse osmosis unit suits species that need soft water and marine aquariums.
A common mistake is choosing a filter and heater that only just cover the tank volume. A little spare capacity makes the system more stable. Spare parts such as filter sponges, impellers and seals are best bought before the old ones wear out.
Related guides
All guides
Equipment5 min read5 sections
Aquarium lighting: how to choose a light
Choosing aquarium lighting step by step: open tank or a tank with a lid, tank length, LED modules for a cover, light control and a night light.
Read the guide
CO25 min read5 sections
Sodastream cylinder adapter: thread and regulator
Sodastream cylinder adapters by the makers' data: the W21.8×14 thread, Quick Connect, working pressure, seals and the makers' safety steps.
Read the guide
Light4 min read5 sections
Aquarium light for plants: LED, photoperiod and light demand
How to choose aquarium light for plants: LED lamp, a photoperiod of about 8 hours, low, medium and high light demand of plants and the link with CO2.
Read the guide