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The Goldfish Gazette, Issue #029 -- Water Changes
May 31, 2016

Goldfish Care Tips and Guidelines

A Free Monthly Resource For Goldfish Enthusiasts
May 2016
Issue #029

In This Issue
Water Changes-Calculating How Often

Water changes are the simplest and most effective way of providing our Goldfish with the basic care needed so they will live a long and healthy life.

Yet every publication and website seems to have a different opinion on how often and how much water we should be changing.

Water Changes-Calculating How Often

The advice given ranges from 10-25% weekly water changes, to as long as monthly changes. Many will give volume and frequencies figures, but qualify them by saying that your particular circumstances may be different.

In fairness to the websites or publications, they know that water changes for Goldfish are vital if they are to thrive, not just survive.

What they should be saying is, water changes are very important, and you must work out how often you need to change the water...because there is no single right answer!

The problem is, several important parameters affect how often the water should be changed. These are:

1. The size of your aquarium or pond
2. The size of your Goldfish
3. The number or density of your fish per gallon/liter
4. What you are feeding you Goldfish, how much and how often
5. Whether you have any filtration
6. The amount of light your aquarium/pond receives
7. The season.

As you can now appreciate, there are too many variables for any publication or website to start giving advice about how often, and how much water should be changed. Only you can decide.

Test Your Water Supply

A good start to working out how often to change water is to test your fresh, clean water supply. Goldfish are very adaptable to different water conditions, so for example if your pH level is a little above or below the ideal, you will know what the normal unpolluted level is.

After testing your water supply, you have some figures to compare against the ideal Goldfish water parameters. These are:

1. pH level 7.4
2. Nitrate level less than 20 ppm (parts per million)
3. Ammonia level zero.

Water from your tap should have nitrates near zero, ammonia at zero, and a pH level around 7.0, but pH can vary depending on location.

There are other chemicals in your water supply such as silicates that have an effect on the growth of brown algae (diatoms) but the important ones for your Goldfish’s health are the three listed.

Goldfish are quite tolerant of high nitrate levels, but there is some evidence that high levels can cause swim bladder disorders.

Test Until Your Water Starts To Become Unclean

Starting with a clean aquarium, and a filter that is established (the aquarium has gone through the ammonia cycle), use a water test kit to test the water daily. As soon as any one of the three parameters, pH, nitrates or ammonia start to move too far away from the ideal, a water change is required.

You will now have an indication of how fast the water starts to degrade from fresh.

In an established aquarium, ammonia shouldn’t be a problem if the filter is doing its job. If ammonia does start to build above zero, check that your filter is big enough for the job, or that nothing has died unseen in the aquarium.

By making say a half (50%) water change, and retesting your water, the pH should be up, the nitrates half what they were, and ammonia at zero.

But is this enough? When do you need to make another water change?

Partial Water Changes Only Remove Some Of the Pollutants

If you keep testing the water daily until it starts to show signs of pollutants rising again, you will notice it is a lot quicker than when the aquarium was clean. This is because with a half water change you have only removed half of the pollutants.

Each time you do a half water change or less, the water that is left is becoming more and more polluted.

The point I am trying to make is this, partial water changes only remove some of the pollutants, and to keep ahead of the build-up, you would need to make more and more frequent water changes. The ideal is to make complete water changes often.

This doesn’t mean stripping down the aquarium or pond, it is just the water you are changing.

Make Large Water Changes Often

Most Goldfish experts make large water changes, and often.

They know that by providing high quality water for their fish, very rarely will their fish succumb to disease or parasites. Poor water quality is the number one reason Goldfish become stressed and get sick.

I make three quarter (75%) water changes weekly in my aquariums, and use a water conditioner when re-filling. Every month or so depending on the season I completely change the water.

Use your water test kit to make sure the volume and frequencies you are changing your water at ensures the water never moves far from the ideal quality.

Your Goldfish will love you for it!

To read more about water changes click here...

Comments? Ideas? Feedback? I'd love to hear from you. Just reply to this e-zine and tell me what you think, or what topics you want covered.

Next Month's Topic

Setting up a Goldfish aquarium

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