The quality of the water used whether in aquariums or aquaponics is essential for the health of your system because it is not only used by fish but also by plants. Having very good water quality is therefore the basis if you wish to embark on these two activities.

We are going to review five possibilities for filling your aquarium or aquaponic tank and we are going to start with the worst thing to do.

1- Take water from a pond, marsh or stream

The worst thing to do would be to take water from a pond, swamp or stream. Why? Quite simply because people bathe in it and there is rubbish. There can be industrial pollution, as well as herds by all kinds of pathogens. In France alone, for example, as there is a lot of agriculture and farmers use a lot of pesticides, we find there a lot of concentrations of pesticides in the waterways and this is then found not only in the products grape harvest, but also in water which is dangerous for fish. However, for a given place, it can be either very good everywhere, or very bad.

So when you choose your pond or stream, it can be very good or really not good. And unfortunately, this cannot be known by simply looking at the water. So the pollution is really very variable and localized. Even if we can treat this water, it is not worth the time or the money.

2- Rainwater or catchment water

In general, there are not too many pathogens. These are waters that are captured from a shallow depth. This may, however, contain biocides from agriculture. There may therefore also be some concerns since it may be close to a septic tank or may have been used as a septic tank. So you have to be careful. Always remember to test your water.

How to test your water?

These days, there are plenty of websites that sell kits to test your water parameters. You can also have your water tested by placing an order online. You will then receive a small kit on which you will put the water that you have collected from your well or your borehole. They will test for color, nitrates, nitrites, germs, etc. They will answer your question. Is this water drinkable and if it is drinkable, this will mean that you can put it in your aquarium or in your aquaponics tank

One thing to be careful though if you take this water. This can be stored in stone or cement and therefore there may be a hardness problem, a pH problem too. And once in a while, there might be too many minerals, calcium, phosphorus, potassium, magnesium, etc. So don't hesitate to test your water.

Rainwater is almost perfect since it is not loaded with minerals. Still need to store it properly. It needs to be harvested and stored properly. An underground system is good because it's going to be cool and out of the light.

3- Reverse osmosis water

Reverse osmosis water is 99.9% pure water, without mineral salts, without chlorine, without metals, without residue, without organic matter, etc. And there are two ways to obtain reverse osmosis water. The first is to go to a pet store. In general, when you catch fish, you can find some kind of pump where you can fill your tank.

Or, if you have a well or borehole water but you just want to filter this water, you can buy a motor bone which will allow you, from this borehole or well water, to obtain reverse osmosis water.

How much water will you need?

You will need water not only to fill your aquarium , your tank, but also to change the water. It should be noted that the water goes away by evaporation on the side of the aquaponics, and, it is necessary to change the water on the side of the aquarium in order to remove the nitrates. You should therefore estimate your consumption and see which is the easiest for you.

4- In third position, the DS Humidifier.

The latter removes the water contained in the air and reduces the humidity in a room. This produces about 20 to 25 liters per month. We can therefore say that this water is pure and we will be able to use it for our aquarium or for our aquaponic system. On the other hand, at the economic level, it does not make sense because one should not buy a humidifier to obtain pure water.

However, if you have one, you have water that is pure and therefore you can use it. However, a small concern that there could be with this water is that the water that is produced may contain traces of metal. This metal comes from the humidifier itself. So it condenses on metal parts and actually may have some metal residue. Copper, aluminum, zinc in things that are not very good, neither for us, nor for plants, nor for our fish. We may also have a few pathogens and fungi from time to time depending on how to start, store temperature, etc...

5- Tap water

It depends where you are in the world, but we still have a source of water close to us which is “city water”. The small concern is that to treat all the pathogens, there will be an addition of chlorine, fluorine, etc… and that there could be a lot of substances added to meet the standards, in particular European ones. The problem with chlorine is that it will be harmful to our bacteria.

Little tip to know: chlorine evaporates easily in a few hours in the open air. If you have an outdoor tank and the tank has been filled with tap water, after a few hours or a day you will have no more chlorine.

6- A little bonus: Mineral water

An alternative to tap water that we don't necessarily think of is to buy mineral water. If your tap water is really bad and by chance it was going to kill all your new little fish .