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Water Chemistry for Discus

Now that you have the location where you are going to place your discus aquarium, and know which aquarium you are going to use, it is time to talk about water.

Discus are very particular about the water chemistry they require to survive in an aquarium.

They need the water temperature to be between 80 degrees and 86 degrees Fahrenheit, the water hardness should be between 3 degrees dH and 15 degrees dH, and the pH levels need to be maintained between 5 and 6.

Since discus are so picky about the water chemistry you will need to take the following things into consideration when preparing the aquarium water for the arrival of your discus: Frequent Testing; What’s on Tap; Hardness and Alkalinity; Controlling water hardness; pH Levels; and Filtration methods.

Frequent Testing:

As with any aquarium set up, you will need to test the water chemistry frequently, to ensure that it is right for your discus. You will need to pick up at least two testing kits, for any eventuality that may occur. Having two testing kits on hand ensures that you won’t run out of the testing chemicals quite so rapidly, and if something unforeseen should happen to your testing kit, you will have a spare.

Before putting water in the tank, you will need to first check it for levels of chlorine and and chloramines. Be sure to have on hand a decent amount of dechlorinator, as most tap water is chock full of it.

The main things you will be testing for on a regular basis are nitrate levels, pH levels, alkalinity, phosphate, iron, and CO2.

You will want to test the water in your discus fish tank at least once daily, if you have a few fish, and two times or more daily if you have a whole herd of them.

What’s on Tap:

Where the water comes from that you are going to be using for your discus tank is of course a major thing. As mentioned earlier, most tap waters have very high levels of chlorine, and chloramines, as well as a variety of other chemicals such as fluoride and possibly even bromine. It can take quite some time to properly prepare the water so it can be used in your discus tank. You will of course need to eliminate the chlorine and chloramines from your tap water before it can be used for your discus fish tank. There are a couple of ways you can remove the chlorine from the tap water to make it suitable for your discus. The most popular methods of getting rid of the chlorine in your tap water are: using a commercial dechlorinator, using activated carbon, letting the water age, aerating the water, and osmosis or de-ionizing.

Using a Commercial Dechlorinator:

By far the easiest method of removing chlorine and various other chemicals from the water, if you are going to be changing out the water, or expect to be changing out the water frequently in your new discus fish tank, you will need to have an ample supply of commercial dechlorinator on hand. It is recommended that you have at least four gallons on hand at any given time, just to save yourself a trip to the aquarium supply store.

Most aquarium supply stores sell dechlorinator, if you don’t have an aquarium supply store near you, you may find some brands of dechlorinator at your local pool supply store.

Using Activated Carbon:

Filtering the water using activated carbon is a filtration method favored by many discus fish keepers and breeders. By pre-filtering the water you are going to use for your discus fish tank, you are really killing two birds with one stone. Once you have the Active Carbon set up, you may just be able to use the same set up for the filtration set up for your new discus tank, saving yourself some time.

Letting the water Age:

By letting the water age, you are giving the chemicals a chance to dissipate on their own. This is really a hit and miss approach, as there is no concrete way of knowing how long it will take for the chemicals to dissipate from the water. It could take two weeks, or it could take a month or more. This method is really only to be used as a last resort if you don’t have access to the things you need to clear out the chemicals on hand.

Aerating the Water:

Simply aerating the water will help to get rid of the chemicals in the local water supply. This can be achieved by using a spray apparatus and spraying the water from container and back into the sprayer multiple times, or if you have an aerator from an aquarium handy, that will work as well. This method will not work on all chemicals however.

Osmosis or De-ionizing:

if you are going to pre-filter your water using osmosis or de-ionization you will need to remember that as you are doing so, you are also removing vital components which will need to be re-added to the water later, before it can be used in the discus fish tank. This method is not recommended for beginners, as it involves a lot of extra work at the end.

It is important to note that chloramines are a mixture of chlorine and ammonia, and cannot be removed by anything other than a very specific dechlorination product.

Of course if you do not wish to go through all the trouble of calibrating the water from your tap, you can always buy water which has the specific qualities that your discus require. Finding said water is no easy task. There are very few aquarium supply stores which sell aquarium ready water, and even if they do, chances are they don’t sell water which is appropriate for discus fish tank usage.