Raise your pH Up to the high side of the zone for excellent health

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Symptoms; goldfish gasping at surface; goldfish at or close surface; redness of gills; goldfish upside down on the bottom; goldfish has bleeding eye

pH up or down? Something is keeping oxygen from entering the water if the pH levels in your tank or pond water are much lower than your tap water. In order for a body of water to support oxygen, it must have a healthy KH level, be free of gases. It must also have the right kind of action and be exposed to fresh air. Then, and only then will the water’s potential of hydrogen or pH levels remain consistently at healthy

What is pH?


Water is low in oxygen if goldfish hang out closer to the top than the bottom of their fish house. The higher the goldfish, the lower the oxygen levels. Click on the link below to increase oxygen levels in water 

911 Water Change

Learn how to buffer by reading Step 9 Water Parameters

Carbonate hardness gives our water the ability to support oxygen. Test KH first and foremost. The comfort zone is 100 to 140 ppm. Buffer if necessary

Test pH. The comfort zone is 7.4 to 8.4. Whenever KH is well within the comfort zone, pH should follow suit


Carbonate mineral gives water the ability to support oxygen, however, it must also be free of carbon dioxide. Co2 is a gas created from the waste goldfish produce. Water must be free of gases and clouds in order to absorb oxygen from the surface.
Water must also be exposed to fresh air, and also if the surface is disturbed. Surface movement helps pull oxygen from the air. We call this method of diffusion

Buffering pH

Test water parameter frequently

Green water (free forming algae) can also fill a body of water keeping oxygen from entering. Green water algae is as easily eliminated as carbon dioxide. If your goldfish house has green water, your fish aren’t getting the oxygen they need, and pH levels are probably low. The only healthy algae is substrate algae, and this can only be obtained when there is enough water movement to push the free floating algae on to substrate

Algae the living plant

The three year old fantail in the photo survived a pH crash, living for another 10 years. If you look closely, however, you’ll see that the eye is bleeding

pH up

Goldfish use less oxygen in colder water. Lower tank or pond temps if possible by chilling tank or pond water; one pitcher at a time to reduce the risk of injury due to prolonged oxygen deprivation Oxygen deprivation anoxia

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Author: Brenda Rand