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How to do the waterchanges that will keep your tank and fish healthy.

What necessary

Buckets, tubes, thermometer, watertreatment. Optional:

How often should waterchanges be conducted.

In the early years of aquariumkeeping people hardly ever did waterchanges. A mysterious disease which was known as the spring plague was well known and feared by all aquariumkeepers. Nowadays it can easily be explained, the temperatures started to rise, and the already foul water in the tank suddenly turned into a poisonous environment, killing nearly all the fish in the tank. This little example does not mean you can change the water yearly, since even though they only added fresh water to the tank, filters were cleaned weekly, and all dirt present in the tank was vacuumed weekly as well.

The other extreme option is daily waterchanges, often this is done by breeders to get fish to spawn. From the fish point of view, this would be the ideal situation. But if you don't want to breed fish, and just want to enjoy a tank, this is a bit overdone.

So how often should you change the water in the tank. Well, it depends. It depends on a lot of things actually. To name but a few; the amount of fish in a tank, the type of filtration, which filter medium, the temperature, the light, how many plants, the size of a tank, the waterchemistry, and ofcourse which fish are present in a tank. If you keep Discus fish for example, which require pure water, and are very susceptible to pollution, you'll have to do more frequent waterchanges. If on the other hand you keep easier more hardy fish(see beginner fish), like the three spot gourami,White cloud mountain minnows, or Corydoras paleatus, you won't need to do so many waterchanges to keep the fish in a good condition.

For the average community tank, 80 cm-100cm, a bit overstocked, an external filter with active charcoal, and a temperature of 24 degrees, a waterchange of 30 % every three to four weeks will suffice. If you keep only a few fish, or if the temperature is lower, a larger tank, feed only a little and so on, you may increase the interval to a maximum of 2 months. On the other hand, if you have a smaller tank, no live plants, feed too much, keep fish that pollute a lot, have a small filter, you should increase the frquency.Do not increase the amount of water you change to compensate!!! Large waterchanges in polluted tanks will cause shocks to the fish, which may die from the sudden changes in the waterchemistry, or weaken from it and may easily contract diseases.


How to change the water.

First of all you'll need to prepare the water you are going to use for waterchanges. If the water that comes out of the tap is high quality, and/or if you use waterconditioners this may not be necessary. Check out the water section or setting up a tank to find out how to prepare water.

Second you'll have to remove water from the tank. This can be done using a tube and a bucket. Place one side of the tube in the tank, and suck on the other end of the tube till the water starts to run(with a bit of practice, and a long enough tube, this can be done without getting water in your mouth). If the water is running, you may use the end in the tank to also remove some dirt present in the tank. If the bucket is almost filled, remove the tube from the tank, and empty the bucket in the toilet. Remember that aquarium gravel can clog pipes very efficiently. Aquarium water can be used to water plants(unless you use a lot of chemicals or salt), which will welcome the dissolved nutrients. The easiest method to remove water from the tank is to have(buy) a long tube, long enough to place one end in the tank, and the other in the garden,toilet, or rainpipe.

After you've finished removing the water, you can start to fill the tank again. The water you're adding should have approximately the same chemical composition, and the same temperature as the water in the tank. To add the water to the tank you can use the same method as above, but here the bucket should be above the tank, or you may add it with a cup. It should be added slowly! So do not empty the bucket in the tank all at once. This may cause temperature changes which can break the glass, stir up the gravel and plants, and is stressful for the fish.

Basically this is all there is to know about waterchanges. It is also recommended to combine this with filtercleaning and the surface cleaning of the gravel.

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