Water changes

Water changes



By Terry Ranson




"My fish were doing fine - until they all died."



I wish I had a nickel every time he heard that line. Most people think their fish are healthy as long as they are able to swim. That's like believing a person is healthy as long as he is breathing. Like people, fish can live for quite a while under less than perfect conditions. Often, fish won't even show signs of distress until the day their keeper finds them belly up in the aquarium.



Fish die for many of the same reasons we do; strokes, failure of internal organs, viral and bacterial (systemic) infections, and infections from wounds. In my opinion, fish losses are almost always caused by stress. I keep stress to a minimum by following some simple rules of aquarium hygiene, the most important being periodic water changes.



In addition to siphoning visible waste from the bottom of the tank, this also helps get rid of harmful substances which cannot be seen with the naked eye. In nature, fish are provided water changes every time it rains, or whenever fresh water flows downstream to where fish live. This is called an open system. But fish in small bodies of water such as aquariums (and to a lesser
extent, ornamental ponds) are in what is called a closed system. Closed systems have no natural way to bring in fresh water, so it must be done artificially, i.e., through water changes.



There's no way around doing water changes. No matter how good your filtration, no matter what chemicals or medication you use, no matter what anyone tells you, if you want to keep fish healthy, you must change their water. And I don't mean just adding water when it gets low from evaporation. When water evaporates, it's just the water which leaves. Fishes' bodily wastes, heavy metals and other substances stay in the water in a concentrated, more harmful form. Without water changes, fish wastes and other organic compounds will drop the pH down until it becomes so acidic it becomes stressful.



If you do enough water changes, pH test kits are virtually unneeded. That's why I almost never test for pH. Many times I've had people say things like, "My Cousin Judy never did
water changes, and her goldfish lived for three years - until they all died one day." For the record, a goldfish can live for more than 30 years. Three years is nothing to brag about. And while Cousin Judy's fish may have lasted for three years, she never really got to enjoy the true beauty of her fish.



Fish which thrive exhibit beautiful colors and interesting behavior. Fish which are simply surviving never look their best, and seldom, if ever exhibit breeding behavior. When you do regular water changes, fish breed readily. That's a sure sign aquarium fish are healthy and thriving - not simply surviving.