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The Goldfish Gazette, Issue #050 -- Water Quality
February 27, 2018

Goldfish Care Tips and Guidelines

A Free Monthly Resource For Goldfish Enthusiasts
February 2018
Issue #050

In This Issue
Water Quality

Water quality is the key to successful Goldfish keeping.

Water Quality

I have had several emails recently regarding sick Goldfish.

Usually the diagnosis of the ailment is relatively simple, but before giving advice about a treatment, I always ask the owner to test their water. I do this because poor water quality is the number one cause of Goldfish ailments.

I see no point in the owner curing their fish by putting it into clean water with an appropriate medication, only to put it back into the same conditions it came from or, repeating the behaviors that caused the problem.

Ideal Water Parameters

It is often written that Goldfish will adapt to a wide range of water conditions, and that they are very hardy animals.

Both of these statements are correct to a point. Goldfish do thrive in a wide range of water conditions, hard water, soft water, high and low pH, but this is assuming the water is not polluted. Some enthusiasts believe that their Goldfish water going acidic isn’t a problem because it is well filtered and crystal clear.

This is a misconception.

What is causing the water to become acidic is a buildup of chemicals in the water caused through filtration. Filters convert harmful compounds to harmless, but even harmless compounds in large quantities start to lower water quality.

An example of this is nitrates which are the byproduct of processing waste from the water.

It was once believed that nitrates at any level were harmless to Goldfish, but now there is some evidence that high levels of nitrates cause swim bladder issues.

If your water supply is acidic (within reason), but low in nitrates, then your fish will adapt to it. As long as water is fresh, clean and high in oxygen, Goldfish will adapt. What Goldfish won’t tolerate is low oxygen levels, ammonia and other pollutants.

The ideal water parameters for Goldfish to thrive are pH 7.0-7.4, ammonia and nitrite levels zero, and nitrates below 30 ppm (parts per million). Most good multi-test water test kits include these tests

Food and Water Quality

Goldfish are known for their huge appetites. The reason Goldfish have huge appetites is because your 2” (50mm) Goldfish is trying to grow to its full size (12” or 300mm for common Goldfish) as quickly as possible. There are two problems with this:
1. The amount of waste the fish produce and
2. Poor quality foods.

I was reading the feeding information on a packet of Goldfish pellet food that instructed to feed only what could be eaten in two minutes. The reason for this is not to ensure proper feeding, it is to stop the water being polluted with pellets that would dissolve into dust after a few minutes. This doesn’t suit the way Goldfish feed which is the subject of next month’s e-Zine.

This is another good reason to feed gel foods such as Repashy’s. It holds together much longer, the fish process more of the food, and it contains very little “ash” or indigestible filler.

Large Water Changes

Frequent large water changes is the answer to maintaining high water quality. There is no point changing 10% of the aquarium water each week without proving through testing that 10% is enough to maintain excellent water quality. Even a 50% water change still leaves half the polluted water in the aquarium.

The only way to know when, and how much water to change is by testing new water to establish base readings, then monitor the water daily or weekly depending on the fish numbers until you detect a change. Usually the pH starts to drop. This test is done after the filter has gone through the nitrogen cycle if one is installed.

The same test applies if you aren’t running a filter, but the more dangerous ammonia will be what you are looking for.

In Summary

Keeping your fish in pristine water conditions almost guarantees your fish won't get diseased. It is one of the easiest ways to maintain your fish's health.
Use a water test kit to establish how often and how much water you need to change.

To read more about water test kits and water treatments, 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

Feeding Goldfish

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