Pure water is made up from two hydrogen molecules and one oxygen molecule (H20). However, the water in which you house living aquatic organisms such as fish and plants is much more than a simple combination of molecules. What do you know about the water and how to add water to your aquarium?
Water can be described as hard or soft, alkaline or acid, and acts as a carrier for a wealth of minerals, nutrients, toxins, bacteria (both beneficial and harmful), and pollutants. Providing good water quality means ensuring that all these factors are at the correct level, so that the water In the aquarium is not only safe for fish and plants, but actively encourages their health and growth.
There are many different interactions between chemicals and minerals that alter the properties of water. To make things even more complicated, both plants and fish are found in many different habitats, each with their own water quality parameters. However, the basic principles of water quality and filtration are universal and apply to all aquarium environments.
Before you start to keep any fish, it is best to discover what type of water you have and keep fish that are happy in it. This is easier and more reliable than trying to change the water chemistry. Water companies take the raw water from whatever source and treat it to provide safe drinking water for our homes. That water source could be anything from a hill stream to a subterranean aquifer, and the water could be soft and acidic, hard and alkaline, high in oxygen, low in oxygen, warm, cool, or any variation.
Just as we need clean, fresh air to breathe, fish require clean, fresh water to live in. If the air in our area becomes polluted, we can move to another area. However, if their water becomes unfit, fish cannot move to another water source. And in an aquarium, it is not just a matter of pollution control, ‘but also a question of the water chemistry. For example, fish that live in acidic conditions cannot tolerate alkaline ones. Each fish species needs water suited to its requirements if it is to survive.
Water hardness
This is a measure of the dissolved mineral salts in the water - the more salts, the harder it is. As water passes through rocks and soil, some of the minerals contained in them dissolve into the water. This means that water originating from limestone aquifers is hard, while water from other areas may be softer. For aquarium purposes, hardness is the amount of calcium carbonate (CaC03) measured in degrees of hardness (°dH) or parts per million (ppm). Buy a test kit, check your water hardness, and choose your fish to suit. You might come across the terms “temporary hardness" and “permanent hardness." Temporary hardness can be removed by boiling the water, but permanent hardness cannot.
Tap water
We all take water for granted. It flows from our taps, is clean and clear, and ready for us to drink, but does that make it right for our fish? The water provided by your local water company is treated to render it fit for human consumption. Chlorine gas is commonly used for purification and if it has been heavily used, you will smell it when you draw water from your tap. If you allow the water to stand for 24 hours, the chlorine will disperse. You can speed up the process by using an airstone to agitate the water.
Another chemical added by water companies is chloramine. This is more difficult to deal with, as it does not disperse naturally. If this is used in your area, you will need to buy a water conditioner to neutralize it. (This will also deal with the chlorine.) Check with your water company to see what is added to your water. If you get on friendly terms with them, they will also let you know if they are intending to flush the water mains with anything to kill bugs that may affect fish.
Other pollutants of tap water include nitrates and phosphates that leach into the water from agricultural fertilizers. Levels can vary over the course of the year.
How to fill your tank
The pH scale
The pH scale is used to determine the acidity or alkalinity of the water. It runs from 0 (extremely acidic) to 14 (extremely alkaline), with 7 being termed neutral. It is a logarithmic scale, each step being 10 times the previous one. This is why seemingly small changes can have dramatic effects. Test kits and electronic meters are available to measure pH.
Tank hygiene
If you use a bucket, make sure that it is free of any residues of cleaning products. It is much better to keep a bucket solely for aquarium use.
Previous article: Choosing and Cleaning Aquarium Rocks
Next article: Running the Tank System before Adding Plants
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Adding the water to fish tank |
Water can be described as hard or soft, alkaline or acid, and acts as a carrier for a wealth of minerals, nutrients, toxins, bacteria (both beneficial and harmful), and pollutants. Providing good water quality means ensuring that all these factors are at the correct level, so that the water In the aquarium is not only safe for fish and plants, but actively encourages their health and growth.
There are many different interactions between chemicals and minerals that alter the properties of water. To make things even more complicated, both plants and fish are found in many different habitats, each with their own water quality parameters. However, the basic principles of water quality and filtration are universal and apply to all aquarium environments.
Before you start to keep any fish, it is best to discover what type of water you have and keep fish that are happy in it. This is easier and more reliable than trying to change the water chemistry. Water companies take the raw water from whatever source and treat it to provide safe drinking water for our homes. That water source could be anything from a hill stream to a subterranean aquifer, and the water could be soft and acidic, hard and alkaline, high in oxygen, low in oxygen, warm, cool, or any variation.
Just as we need clean, fresh air to breathe, fish require clean, fresh water to live in. If the air in our area becomes polluted, we can move to another area. However, if their water becomes unfit, fish cannot move to another water source. And in an aquarium, it is not just a matter of pollution control, ‘but also a question of the water chemistry. For example, fish that live in acidic conditions cannot tolerate alkaline ones. Each fish species needs water suited to its requirements if it is to survive.
Water hardness
This is a measure of the dissolved mineral salts in the water - the more salts, the harder it is. As water passes through rocks and soil, some of the minerals contained in them dissolve into the water. This means that water originating from limestone aquifers is hard, while water from other areas may be softer. For aquarium purposes, hardness is the amount of calcium carbonate (CaC03) measured in degrees of hardness (°dH) or parts per million (ppm). Buy a test kit, check your water hardness, and choose your fish to suit. You might come across the terms “temporary hardness" and “permanent hardness." Temporary hardness can be removed by boiling the water, but permanent hardness cannot.
Tap water
We all take water for granted. It flows from our taps, is clean and clear, and ready for us to drink, but does that make it right for our fish? The water provided by your local water company is treated to render it fit for human consumption. Chlorine gas is commonly used for purification and if it has been heavily used, you will smell it when you draw water from your tap. If you allow the water to stand for 24 hours, the chlorine will disperse. You can speed up the process by using an airstone to agitate the water.
Another chemical added by water companies is chloramine. This is more difficult to deal with, as it does not disperse naturally. If this is used in your area, you will need to buy a water conditioner to neutralize it. (This will also deal with the chlorine.) Check with your water company to see what is added to your water. If you get on friendly terms with them, they will also let you know if they are intending to flush the water mains with anything to kill bugs that may affect fish.
Other pollutants of tap water include nitrates and phosphates that leach into the water from agricultural fertilizers. Levels can vary over the course of the year.
Filling the tank
The easiest way to fill your tank is with a pitcher. At this stage you can use cold or warm water, as no livestock or plants are present. Gently pour the water over a flat stone to avoid disturbing the substrate too much. It takes time but is better than destroying your aquarium decor. If you have no suitable stones in your setup, pour the water into a saucer.How to fill your tank
- Use a clean pitcher to start filling the tank. As the water level rises, you can add the water by slowly pouring from a bucket, checking that it is not disturbing the substrate too much.
- The more you clean the gravel before you put it in the aquarium, the less likely it is to cause cloudiness as you add the water. Once the aquarium is full, carefully rearrange any substrate you have disturbed by too-vigorous pouring.
The pH scale
The pH scale is used to determine the acidity or alkalinity of the water. It runs from 0 (extremely acidic) to 14 (extremely alkaline), with 7 being termed neutral. It is a logarithmic scale, each step being 10 times the previous one. This is why seemingly small changes can have dramatic effects. Test kits and electronic meters are available to measure pH.
Tank hygiene
If you use a bucket, make sure that it is free of any residues of cleaning products. It is much better to keep a bucket solely for aquarium use.
Previous article: Choosing and Cleaning Aquarium Rocks
Next article: Running the Tank System before Adding Plants