Water treatment

How to turn tap water into the right aquarium water

Depending on the country and region you live in, your tap water may contain unsuitable or harmful substances for your aquarium inhabitants. A water conditioner can neutralise these problem substances and turn your tap water into aquarium water.

But even then it is still tap water (without pollutants), not tropical water with the typical humic substances that are staples for most tropical fish! Therefore, with JBL Tropol there is a tropical water conditioner that cannot bind any pollutants, but adds the essential humic substances to your water so that your fish feel at home, show more beautiful colours, grow healthier and also reproduce. And don't worry: JBL Tropol does not turn your aquarium water brown like the blackwater in South America. It only supplements the important humic substances so that your water remains crystal-clear and only gets a barely visible brown tinge - we promise!

True blackwater with altum angelfish in Colombia
Left glass: pure tap water, middle: heavily overdosed, right: correctly dosed JBL Tropol

The 3 types of natural habitat waters:

1. Clearwater:
Lake Tanganyika/East Africa

Clearwater rivers mostly come from the mountains, are cooler than lowland rivers and are much less species rich than blackwater or whitewater rivers. In addition to mountain rivers with clearwater, there are a few other clearwater regions in the tropics, but they are in the minority. Typical clearwater biotopes can be found in the Pantanal in South America, on the west coast of Florida, the two rift valley lakes Tanganyika and Malawi in Africa and, of course, in isolated bodies of water worldwide. However, as soon as larger amounts of humic substances are present, clearwater changes to blackwater, which can remain clear but has a medium to dark tinge.

Pantanal/South America
Рио-Кларо (Колумбия)
2. Whitewater:

Rivers that rise in mountains and carry minerals from the mountains are called whitewater rivers. The best known whitewater river is the Amazon, before it joins the blackwater river Rio Negro at Manaus. Whitewater is quite opaque and, unlike most blackwaters, has degrees of hardness due to the minerals it contains.

Underwater in the Solimoes, the Amazon River before it joins the Rio Negro
At Manaus the whitewater river Solimoes joins the blackwater river Rio Negro
3. Blackwater:

The Rio Negro in Amazonia is one of the most famous blackwater rivers in the world. Even its name, Negro, indicates its dark colour. It is warmer than the nearby clearwater and whitewater rivers, because a dark water colour warms up more than a lighter water colour (Rio Negro 30 °C, Solimoes 28 °C). Anyone who’s changed a black T-shirt for a white one in the blazing sun will know this! The black water, which is absolutely clear, gets its dark colour from a large number of humic substances that come from the soil of the region through which the river flows.

The clear blackwater of the Rio Negro
In the Rio Atabappo/Colombia

What is blackwater?

This video, filmed in a blackwater biotope in Colombia, shows you what real blackwater looks like and which fish species live there.

These substances can be present and this is how you can solve the problem

These substances can be present and this is how you can solve the problem

Depending on the quality and location, tap water contains several substances we could well do without in the aquarium. Furthermore some types of water may be unsuitable for the fish, plants and invertebrates you keep.

Chlorine (and other disinfectants)

Waterworks sometimes or regularly use chlorine to sterilise (disinfect) the tap water. You can neutralise the chlorine with the help of a water conditioner ( JBL Biotopol , JBL Biotopol R ).

Heavy metals

Water pipes consist of metals which reach tap water as ions (charged particles). These can be lead, copper, zinc or others. A good water conditioner, such as JBL Biotopol or JBL Biotopol R (for small aquariums) encases these heavy metals (chelates them) and makes them harmless.

Copper

Is also classified as a heavy metal and is deadly for invertebrates like shrimps. A water conditioner such as ( JBL Biotopol C encases and neutralises copper. Instead of JBL Biotopol one better uses JBL Biotopol C when keeping invertebrates.

Pesticides & herbicides

If you live in agricultural regions there is a high probability that these problematic substances reach your tap water through groundwater. With good activated carbon ( JBL Carbomec ultra ) you can reliably and quickly remove both substances from your water. Unfortunately water tests to determine pesticide and herbicide content do not exist.

Soft water

Some regions have very few minerals in the mains water. Low-mineral water is known as SOFT water. This is ideal for many fish, invertebrate and plant species. However, the pH value is often not stable. With water hardener salt ( JBL Aquadur ) you can harden the water to some extent and stabilise the pH level. If you want to keep fish from Lake Malawi and Lake Tanganyika you need medium-hard water. With the special salt JBL Aquadur Malawi-Tanganjika you can turn your soft water into harder water.

Hard water

In some regions tap water can have a high calcium and/or magnesium concentration. Both substances increase the general hardness of the water, making your tap water hard. You often see this in the form of limescale in your bathroom or kitchen. With the help of a reverse osmosis system you can produce almost mineral-free water. You can mix it with your harder tap water until the desired degree of hardness has been reached. Ideally add a special reverse osmosis salt ( JBL Aquadur ) to precisely adjust to the desired hardness.

Reverse osmosis water

With the help of a reverse osmosis system you can produce almost mineral-free water. You can mix it with your harder tap water until the desired degree of hardness has been reached. Ideally add a special reverse osmosis salt ( JBL Aquadur ) to precisely adjust to the desired hardness.

Well water

Well water can be very suitable or not suitable at all for your aquarium water. Here you should carry out a complete analysis to check its suitability. It is important to check: GH, KH, pH, NO2, NO3, PO4, Fe.

When and how exactly is the water conditioner used?

If you use a bucket to carry out your partial water change it’s simple: always add your dose of water conditioner to the bucket, e.g. for the 10 l bucket contents. However, if you are using a hose, add your dose of water conditioner to the aquarium after the siphoning and BEFORE you add new water.

This way, harmful substances in the tap water, such as chlorine or lead, can be bound immediately before they cause any damage. However this method could prove fatal for shrimps and invertebrates, since they must NOT come into contact with any copper present in the tap water. If you keep shrimps and invertebrates only the bucket method is possible, because here any copper in the bucket is bound by the water conditioner BEFORE it enters the aquarium.

Why do we need a water conditioner for the aquarium?

Have you found yourself asking whether you really need a water conditioner for your aquarium? Which substances in tap water are harmful for our aquarium inhabitants and how can they be neutralised?

Webinar about water treatment

Water treatment is explained here in detail with examples and small experiments. Biologist Heiko Blessin shows what a water conditioner does in a way that even non-chemists can understand. What effect does a water conditioner have on shrimps and why doesn’t the packaging of Catappa leaves say what they really do?

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