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What Causes High PH Levels?

| Updated September 26, 2017

Owning a fish tank involves being aware of pH levels on a weekly basis. New water, a dirty tank or unwanted chemical substances can cause pH levels to fluctuate. Assessing pH balances, knowing what level fish require, and how to fix the problem are keys to keeping correct pH numbers.


i Image by Flickr.com, courtesy of Matt Brown

According to www.fishtankguide.net, pH is a measure of the acidity or alkalinity of a substance. A scale of 1 to 14, with 7 being neutral, is used. Under 7 is acidic, with above 7 recorded as alkaline. Water naturally has a pH of 7, but the fluid used at home is different due to chemicals suspended or dissolved in the water.


i Image by Flickr.com, courtesy of Jelene Morris

Adding tap water to a freshwater tank can cause pH levels to shoot up quickly. Reef tanks encounter problems when limewater is added. High pH alkalinity supplements added too fast raise levels, according to www.advanceaquarist.com. Systems can fluctuate with the placing of a hand, fish bag from a store, decoration or different fish food into the water.

Tank Care

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Waste products from fish will raise levels if not properly exported with a filtration system. Body excrements, compounds in the water, and other "dirt" from food particles may raise pH.

Assessing PH

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High levels of pH are checked when changes occur to the tank. Bottles of chemical strips supplied at local pet stores or big chain supermarkets can be utilized by sticking the strip in a sample of water from the tank and matching colors.

Reducing High Levels

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Better aeration will add carbon dioxide in the water. For reef tanks, adding vinegar directly to the limewater itself or into the tank will help. Store-bought solutions are also available for freshwater tanks.