Freshwater
Freshwater aquariums, filters, lights, heaters, CO2, substrates, fertilisers and live plants.
Advice and care
How to choose freshwater aquarium equipment
Start with the volume, then pick the equipment and livestock that suit that tank.
Volume first
Pick the tank before the equipment: filter and heater are chosen by litres.
Plants or fish
A planted tank needs nutrient soil, fertiliser and a stronger light than a fish-only tank.
Time to cycle
Let the filter run for a couple of weeks and test the water before adding fish.
Frequently asked questions
Which aquarium suits a beginner?
A medium-sized set with the filter, light and heater already matched. Water values change more slowly in a larger tank than in a very small one.
Does a planted tank need a CO2 system?
Easy plants such as anubias, ferns and mosses grow without CO2. Dense carpets and red plants need CO2 and a stronger light.
Read more
Freshwater aquarium equipment works as one system, so the parts have to match. Filter and heater output are chosen by volume in litres, and the light by the tank's length and how demanding your plants are. If the equipment is too weak for the tank, careful maintenance will not make up for it: the water clouds and the temperature drifts.
The second decision is whether the tank is mainly for plants or for fish. A densely planted aquarium needs a nutrient-rich substrate, regular fertiliser and often added CO2; a fish tank does well with gravel, a good filter and a few undemanding plants.
The most common mistake is stocking too quickly. A new filter has not yet grown the bacteria that break down fish waste, so add fish gradually and check ammonia and nitrite with tests. After that, a weekly partial water change keeps the water clean.
Related guides
All guides
Beginners5 min read6 sections
Aquarium care: daily and regular maintenance
Aquarium care after the start: what to do every day, how to change part of the water, clean the gravel, glass and filter, and test the water.
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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.
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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.
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