Why might freshwater aquarium water need conditioning?
Tap water can be a suitable starting point. Whether it needs treatment depends on its composition and the requirements of your fish and plants. Drinking water quality alone does not mean that it provides suitable conditions for every aquarium species.
Many species from the Amazon region in South America, for example, come from soft water. Lake Tanganyika, by contrast, is in East Africa and contains mineral-rich, alkaline freshwater. Requirements also vary within a region. Find out what the particular species you intend to keep need.
Can you use fresh tap water in your aquarium?
First check your water supplier’s information and measure the parameters relevant to your livestock, particularly temperature, pH, general hardness and carbonate hardness. Further checks may be useful depending on the source water.
If chlorine or chloramine is present, treat the replacement water with a suitable method or conditioner, following its instructions, before it comes into contact with the animals. Tap water cannot be described as always unsuitable or necessarily free from chlorine in a particular region.
Match the treatment to the species you keep. Soft-water fish and species from mineral-rich lakes have different requirements. Mineral-rich freshwater is not the same as brackish or salt water.
When is reverse osmosis useful for freshwater aquariums?
A reverse osmosis system can help when your tap water contains too many dissolved minerals or other unwanted substances for the intended livestock. It reduces many of these substances and allows targeted further conditioning.
Rejection depends on the membrane, source water and operating conditions. Do not assume that low-mineral permeate can be used unchanged for every freshwater fish: provide the mineral content and water parameters required by your species.
Do you need to add trace elements to fresh water?
The need for supplementation depends on the source water, livestock and plants. Tap water is not necessarily free of trace elements. Water from which most salts have been removed may need targeted remineralisation.
Choose supplements to suit your aquarium’s needs and follow the product instructions. Avoid adding more simply on the assumption that more is better.
Do freshwater fish need different water parameters?
Yes. Requirements vary with the species and its origin. Many species from soft, acidic waters need different conditions from fish living in mineral-rich, alkaline lakes such as Lake Tanganyika.
Choose livestock with compatible requirements for water parameters, temperature, space and behaviour. A higher mineral content does not make fish generally more tolerant of poor water quality.
What are general and carbonate hardness?
General hardness (GH) mainly describes dissolved calcium and magnesium. It is an important indicator of the mineral content of the water.
The value measured as carbonate hardness (KH) in aquarium keeping describes the water’s acid-neutralising capacity, mainly involving bicarbonate and carbonate. It is important for pH buffering and should not be confused with general hardness.
Measure GH, KH and pH separately and assess them against the requirements of your animals and plants. Make changes in a controlled, targeted way.
Suitable water conditioning starts with the water parameters and the needs of your livestock. Supplement mechanical and biological filtration with appropriate care products or filter media where needed.
Explore our freshwater care products and freshwater filter media. Choose products according to their intended use and monitor changes in water parameters.
What is a freshwater aquarium and how do you set one up?
You need a suitable aquarium, filtration, substrate and an appropriate setup for your livestock. Whether a heater is required depends on the species. Set up the aquarium, prepare the water and start the equipment.
Allow the aquarium to cycle without fish initially. This often takes several weeks, but elapsed time alone does not establish sufficient biological filtration. Check the relevant water parameters, particularly ammonium/ammonia and nitrite, before introducing animals.
How should you maintain a freshwater aquarium?
Carry out regular partial water changes and clean as needed. Check temperature and water parameters, feed according to the needs of your livestock and remove uneaten food. Provide enough space, suitable filtration and an adequate oxygen supply.
Which freshwater fish are suitable for an aquarium?
Guppies, neon tetras, angelfish and catfish are examples of freshwater fish, but their needs differ. Before buying, find out about the particular species, its adult size, behaviour, water requirements and suitable aquarium size. Choose species with compatible needs.
How should you prepare aquarium water?
First check your source water and the requirements of your livestock. Treat any chlorine or chloramine present with a suitable method before the water comes into contact with the animals. Adjust mineral content, temperature and other parameters in a controlled way where necessary. Follow the instructions for the products you use.
Which filters are suitable for a freshwater aquarium?
Internal filters, external filters and Hamburg mattenfilters may be suitable depending on the setup. Choose a system according to aquarium size, livestock, required filtration and maintenance access. Flow and space requirements should also suit your aquarium.
How often should you change the water?
A partial water change of about 20–30% every 1–2 weeks can serve as a guide. The appropriate amount and frequency depend on livestock, feeding and measured water parameters. Prepare replacement water as needed and avoid abrupt changes in temperature and composition.
Which water treatment methods are available?
Mechanical filtration removes particles. In biological filtration, microorganisms established on the filter media transform certain substances. Chemical or adsorptive media bind selected substances depending on the material. Choose filter media for a specific purpose; different materials do not all perform the same task.
How can you reduce algae growth?
Balance lighting, plants, livestock and feeding. Check the water parameters, carry out appropriate partial water changes and remove unwanted deposits mechanically. Algae cannot be eliminated completely; investigate the cause of excessive growth first. Add animals only if their husbandry requirements suit your aquarium.