The-Wolf
Ex-LFS manager/ keeper of over 30 danio species
gH (General Hardness)
WHAT is gH?
You have probably heard the term 'water hardness' referred to in relation to the water which comes from our taps. We see evidence of this every day whenever we use water around the house. The kettle is the obvious place to notice this; the white scaly deposit that forms on the element and sides of the kettle. This is often referred to as 'fur' and is a combination of two major elements: Calcium and magnesium.
It is these two elements which contribute to what we fish keepers call the gH of our aquarium.
WHY does gH affect my fish?
Like all creatures (including us humans!) fish need the correct environment in which to live. As the water is their total environment it is important to ensure that it suits their needs and the degree of hardness of the water can directly affect their well being. Ideally we need to try to mirror in the aquarium the conditions that nature would have provided for the type of fish we keep.
Although fish can be quite adaptable to water hardness, extremes must be avoided if the fish are to live healthy, colourful lives. For example, fish that would naturally live in soft water do not thrive well in hard water; they lose their natural sparkle and appear pale and out-of-condition; they also become much more disease-prone.
HOW do I control gH in my aquarium?
gH is measured using a simple test kit and is read on a scale from 1 upwards,
1 representing the softest water, with higher numbers representing increasing hardness:
Up to 3 Soft
3 to 6 Medium soft
6 to 10 .Slightly hard
10 to 16 Medium hard
16 to 26 Hard
Over 26 Very hard
Most of the fish you buy will be happiest with gH of between 5 and 7, although between 3 and 10 would be acceptable. If your tap water has a very high this means that you will have high levels of calcium and magnesium in the aquarium. This can be countered in several ways:
Peat.
A traditional method, and some would argue the best, is to filter the water over peat. This contains natural softening agents that are released into the water that passes over it. Peat can be added to the aquarium in two ways: either as it is (but this is messy) or it can be put into a filter bag(or a stocking) which can then be simply placed in the aquarium or placed inside a power filter (internal or external types are both suitable).
Blackwater extract.
You can use a blackwater extract which will decrease the hardness. These conditioners also contain nutrients on which plants feed so acting as a good plant fertiliser as well as having a suppressing effect on algae. (it will not cure algae problems but will lessen them.)
Combination.
Use a combination of peat and blackwater extract. This will give you the best of both worlds.
A final method of softening available to the aquarist’s to use Reverse Osmosis (RO) water to soften the tap water before adding it to the aquarium. Although this is an effective way to soften tap water it is expensive and, IMHO, somewhat of a chore.
The main causes of gH problems
possible gravel/ decoration problems; IE unsuitable gravel or rocks etc.
possible high evaporation and topping up with untreated water, increase the regularity of your water changes and don’t forget the de-chlorinator.
kH (Carbonate Hardness)
WHAT is kH?
Carbonate hardness, referred to as kH, (temporary hardness) is simply a measure of the quantity of carbonate 'ions' dissolved in water which contributes a certain 'hardness' to it.
In an aquarium this hardness can be lost over time and how this effects your fish is described below.
A simple way to think of this (although not strictly analogous from the point of view of the chemistry) is to imagine a bottle of lemonade. When first opened it gives a fizz and is lively to taste, but if it is left open overnight it loses its fizz and becomes flat.
Similarly, when you first set up your aquarium, if you live where your local tap water has a relatively high kH value it will seem fresh and 'lively' to your fish. Then, slowly, due to bacterial breakdown of the fishes waste, the water ages and starts to go flat. What is happening is that chemical changes are occurring which cause the kH to reduce.
WHY should I be concerned about kH?
Because your fish thrive best in a balanced environment it is important to try to maintain kH at an optimum level for them.
kH is measured on a number scale from zero upwards. For an average community aquarium a kH of between 5 and 7 is ideal, although a level as high as 10 and as low as 3 can be tolerated by many variety of fish.
Using a test kit you should ascertain what the kH value is in your area & check if this is acceptable for your fish.
Low kH is more of a problem for fish keepers; a zero kH is not safe for your fish and your plants will also suffer and may not grow at all.
In addition kH also affects the stability of the pH (the measurement of acidity/alkalinity) of the water, and low kH can cause the pH to drop to dangerously low levels (the water becomes more acidic) which can harm or even kill your fish.
As mentioned above, the natural process which occurs in your aquarium will cause the kH to reduce and it is important therefore to see how the kH can be maintained at a satisfactory level.
HOW do I control kH?
In fact, kH is quite easy to control. Firstly, you should make regular tests as kH can reduce quite rapidly.
If the kH is too high to start with, which is unlikely if you use our local tap water to fill your aquarium, you can reduce the kH by mixing demineralised (distilled) water with the tap water. Alternatively you can mix previously boiled water (when cold!) with the tap water.
However, the bigger problems occur when the kH of the aquarium water is allowed to drop too low, particularly if insufficient water changes are being made. Regular partial water changes with relatively hard tap water will keep the kH topped-up to an adequate level.
If you have allowed the kH to drop, or it this has happened without you being aware of it, you correct this by carrying out small water changes 10-20% alternate days and adding a commercially available kH Plus. Check the kH after each change until it is brought up to the correct level.
The main causes of kH problems
The most likely cause is either insufficient water changing, or that the source of the water you are using has a kH that is too low.
Most of this infomation was translated from http
/www.sera.de/ and http/www.aquanet.de/sera
Any additional comments, suggestion are welcomed.
I'm currently refining an explination of chlorine and phosphates to add to this topic.
WHAT is gH?
You have probably heard the term 'water hardness' referred to in relation to the water which comes from our taps. We see evidence of this every day whenever we use water around the house. The kettle is the obvious place to notice this; the white scaly deposit that forms on the element and sides of the kettle. This is often referred to as 'fur' and is a combination of two major elements: Calcium and magnesium.
It is these two elements which contribute to what we fish keepers call the gH of our aquarium.
WHY does gH affect my fish?
Like all creatures (including us humans!) fish need the correct environment in which to live. As the water is their total environment it is important to ensure that it suits their needs and the degree of hardness of the water can directly affect their well being. Ideally we need to try to mirror in the aquarium the conditions that nature would have provided for the type of fish we keep.
Although fish can be quite adaptable to water hardness, extremes must be avoided if the fish are to live healthy, colourful lives. For example, fish that would naturally live in soft water do not thrive well in hard water; they lose their natural sparkle and appear pale and out-of-condition; they also become much more disease-prone.
HOW do I control gH in my aquarium?
gH is measured using a simple test kit and is read on a scale from 1 upwards,
1 representing the softest water, with higher numbers representing increasing hardness:
Up to 3 Soft
3 to 6 Medium soft
6 to 10 .Slightly hard
10 to 16 Medium hard
16 to 26 Hard
Over 26 Very hard
Most of the fish you buy will be happiest with gH of between 5 and 7, although between 3 and 10 would be acceptable. If your tap water has a very high this means that you will have high levels of calcium and magnesium in the aquarium. This can be countered in several ways:
Peat.
A traditional method, and some would argue the best, is to filter the water over peat. This contains natural softening agents that are released into the water that passes over it. Peat can be added to the aquarium in two ways: either as it is (but this is messy) or it can be put into a filter bag(or a stocking) which can then be simply placed in the aquarium or placed inside a power filter (internal or external types are both suitable).
Blackwater extract.
You can use a blackwater extract which will decrease the hardness. These conditioners also contain nutrients on which plants feed so acting as a good plant fertiliser as well as having a suppressing effect on algae. (it will not cure algae problems but will lessen them.)
Combination.
Use a combination of peat and blackwater extract. This will give you the best of both worlds.
A final method of softening available to the aquarist’s to use Reverse Osmosis (RO) water to soften the tap water before adding it to the aquarium. Although this is an effective way to soften tap water it is expensive and, IMHO, somewhat of a chore.
The main causes of gH problems
possible gravel/ decoration problems; IE unsuitable gravel or rocks etc.
possible high evaporation and topping up with untreated water, increase the regularity of your water changes and don’t forget the de-chlorinator.
kH (Carbonate Hardness)
WHAT is kH?
Carbonate hardness, referred to as kH, (temporary hardness) is simply a measure of the quantity of carbonate 'ions' dissolved in water which contributes a certain 'hardness' to it.
In an aquarium this hardness can be lost over time and how this effects your fish is described below.
A simple way to think of this (although not strictly analogous from the point of view of the chemistry) is to imagine a bottle of lemonade. When first opened it gives a fizz and is lively to taste, but if it is left open overnight it loses its fizz and becomes flat.
Similarly, when you first set up your aquarium, if you live where your local tap water has a relatively high kH value it will seem fresh and 'lively' to your fish. Then, slowly, due to bacterial breakdown of the fishes waste, the water ages and starts to go flat. What is happening is that chemical changes are occurring which cause the kH to reduce.
WHY should I be concerned about kH?
Because your fish thrive best in a balanced environment it is important to try to maintain kH at an optimum level for them.
kH is measured on a number scale from zero upwards. For an average community aquarium a kH of between 5 and 7 is ideal, although a level as high as 10 and as low as 3 can be tolerated by many variety of fish.
Using a test kit you should ascertain what the kH value is in your area & check if this is acceptable for your fish.
Low kH is more of a problem for fish keepers; a zero kH is not safe for your fish and your plants will also suffer and may not grow at all.
In addition kH also affects the stability of the pH (the measurement of acidity/alkalinity) of the water, and low kH can cause the pH to drop to dangerously low levels (the water becomes more acidic) which can harm or even kill your fish.
As mentioned above, the natural process which occurs in your aquarium will cause the kH to reduce and it is important therefore to see how the kH can be maintained at a satisfactory level.
HOW do I control kH?
In fact, kH is quite easy to control. Firstly, you should make regular tests as kH can reduce quite rapidly.
If the kH is too high to start with, which is unlikely if you use our local tap water to fill your aquarium, you can reduce the kH by mixing demineralised (distilled) water with the tap water. Alternatively you can mix previously boiled water (when cold!) with the tap water.
However, the bigger problems occur when the kH of the aquarium water is allowed to drop too low, particularly if insufficient water changes are being made. Regular partial water changes with relatively hard tap water will keep the kH topped-up to an adequate level.
If you have allowed the kH to drop, or it this has happened without you being aware of it, you correct this by carrying out small water changes 10-20% alternate days and adding a commercially available kH Plus. Check the kH after each change until it is brought up to the correct level.
The main causes of kH problems
The most likely cause is either insufficient water changing, or that the source of the water you are using has a kH that is too low.
Most of this infomation was translated from http
/www.sera.de/ and http/www.aquanet.de/seraAny additional comments, suggestion are welcomed.
I'm currently refining an explination of chlorine and phosphates to add to this topic.
