Osmosis systems for the aquarium

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Osmosis water is used for drinking water treatment. It is also an important component in aquaristics. In the trade there is an abundance of osmosis systems for the aquarium. Aquarists in particular benefit from the large selection, as osmosis systems are specially developed for aquariums. These are adapted to the special requirements.

Nevertheless, it is important to consider whether an osmosis system is necessary and if so, how much osmosis water is actually required for the aquarium. The question also arises as to why the tap water from the domestic tap is not sufficient when it can be supplemented with the appropriate additives. Native fish species have no problems with the treatment water, as they are used to this water. However, the situation is quite different with exotic fish and plant species. This is because tropical specimens react very sensitively to hard water. Over time, the fish can fall ill and even die.

What is an osmosis plant?

The osmosis plant is actually a reverse osmosis plant. The naturalised term “osmosis plant” is simply a perfect high-tech water filter plant. The filter system for the drinking or tap water ensures a drinkable and thoroughly clean water. The water filter on the other hand works with the principle of reverse osmosis. Any kind of dirt is filtered out of the water by an osmosis system.

In unfiltered tap water there is often a large number of substances and also dangerous substances. The concentration of these dissolved substances can be determined using a TDS measuring device. To filter such substances out of the water, which may be dangerous for aquatic life, osmosis systems offer the best method. The substances filtered out in this way are immediately discharged from the osmosis plant directly into the wastewater. Since the tap water does not necessarily meet the requirements of the aquarium occupants, it is possible that they will sooner or later fall ill or, in the worst case, perish. That is why an osmosis plant is especially necessary for exotic aquarium inhabitants.


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Why exactly osmosis water?

The production of osmosis water is the aim of reverse osmosis. This produces pure water, which is called osmosis water. The domestic tap water is often much too hard, in addition, there are often a lot of contaminants in the water. This is bad for the fish. Because the water from the tap can contain undesirable substances and therefore the water quality can be declared as bad overall.

Most fish in domestic aquariums need soft water. Fish that come from lakes and running waters are used to hardness levels between 0.1 and 2 dGH (total hardness of the water – “degree of German hardness”). The hardness of the water from the pipe often has a hardness of 10 dGH and more. Here the osmosis plant works perfectly. The water filter system is not necessarily able to remove all dangerous or questionable substances from the water. However, due to its functional system, an osmosis plant is able to significantly reduce the degree of hardness of the water and thus improve the water for the aquarium inhabitants. That is why passionate aquarium enthusiasts should use osmosis water. Water inhabitants are very sensitive creatures in relation to water. Even though there is no absolutely valid formula for perfect water.

The water is pressed through an ultra-fine membrane (polymer film) in the system with pressure. The result of this process is filtered tap water. The osmosis water has been freed from almost all pollutants during this process and therefore has a high degree of purity. The water hardness of the osmosis water is also convincing and the water is ultimately perfectly filtered and softer. This is also associated with further amenities for the fish and their life in the aquarium. Because the better the quality of the water in an aquarium, the more comfortable the aquarium inhabitants feel.


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When is an osmosis plant useful?

Many owners of aquariums rightly ask themselves the question whether the purchase of an osmosis plant is sensible or unnecessary. The fish cannot give any information in this regard. However, if you talk to passionate tea and coffee lovers, the difference will be quickly explained to you, what the use of osmosis water is all about.

Some people avoid tap water for very specific reasons, as many assume that the water from the tap contains harmful substances and even residues of medication. You can imagine what this means for the aquarium inhabitants. Osmosis water from the plant is an absolutely sensible and also a definitely good solution, because for the fish a hardened water enriched with harmful substances is hardly the ideal environment. Also the pH-value can be lowered with an osmosis plant and this is enormously important for the successful keeping of fish. The water from the pipe should be treated accordingly, only then the animals in the aquarium have an optimal habitat. The osmosis water is perfect for this.

In contrast to a standard water filter for the aquarium, an osmosis system not only filters out coarse impurities that are caused by the keeping of plants and animals, but also viruses, bacteria, fungi, pesticides, nitrates, drug residues and other foreign substances are meticulously filtered out. With an osmosis system the water in the aquarium becomes absolutely pure and at the same time the aquarium owner is able to have full control over the water value in the aquarium.

However, the aquarium should not be filled exclusively with pure osmosis water. The ideal mixing ratio must be calculated. When mixing osmosis water and tap water, the degree of hardness of the two types of water is precisely measured beforehand. With the tap water and the aquarium water the degree of acidity can be neutralized. Thus tap water and osmosis water complement each other ideally. The mixing ratio also depends on the fish population and the desired values.

For example, if the desired ideal value is 5 degrees GH, the aquarium owner needs an osmosis water proportion of approximately 67 percent for his aquarium. Provided that the tap water has a 15 degree GH and the osmosis water a 0.1 degree GH. This means: With 200 litres of changing water in an aquarium, the proportion of 67 percent osmosis water would correspond to 134 litres of pure osmosis water.

Purchase costs and running costs of an osmosis plant

Depending on the model and the quality of the system, the one-off costs of the purchase are between 160 and 750 euros. Financial expenses for maintenance and accessories are added to the running costs. The operating costs include the costs for the rinsing and waste water as well as for the osmosis water. To produce one litre of osmosis water, about three to four litres of water are needed from the tap. The water consumption always depends on how often the basin needs to be cleaned. In summary:

  • Costs for osmosis water
  • Costs for waste water
  • Costs for rinsing water
  • Sediment filter costs
  • Costs for the TFCM membrane
  • Costs for the GAC activated carbon filter
  • Costs for the fine filters and the pre-filters
]The filters should be changed every six months. During the year, the aquarium owner should allow for a cost of 50 to 200 euros, depending on the osmosis system.

Building an osmosis plant yourself

This is not advisable, especially since very strict regulations apply to all devices that are grown or installed in the area of drinking water installations in Germany. Tested systems and sets must have a test seal (DVGW), if known. In addition to the legal difficulties of installing a self-built system, there are also all kinds of technical problems.

FAQ around an osmosis system for the aquarium:

  • Is the osmosis water a completely lime-free water?
    Yes, because of its fine structure only water molecules can pass through it. The process guarantees 100 percent lime-free water for the aquarium.
  • What does osmosis water actually taste like?
    The taste of the water is difficult to judge. But it has a rather gentle taste and is ideal for the aquarium inhabitants.

Buy osmosis plant

Popular osmosis systems for aquariums are available from Amazon, among others. Often they have evaluations and already answered product questions, so that per osmosis plant accordingly much information is available.

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