Home Freshwater Topics Water Quality Water Changes and Its Effect to Fishes

Water Changes and Its Effect to Fishes

Water changes are important aspects of routine tank maintenance. Most aquarists know regular water changes should be undertaken, but not everyone does or knows how to do it correctly.

What are “Water Changes”?
For aquarists, water changes involve removing water from the tank and replacing it with new, clean water. The process helps remove waste and organic matter which are dissolved in the tank water. Removing old tank water also helps eliminate chemicals or medications once the treatment period has been completed.

When organic matter is present in aquarium water, it creates a favorable environment for the buildup of nitrate and phosphate, which many aquarists find a challenge to control. This creates a condition called “old tank syndrome”. Aside from exerting a negative effect on your fish and other tank inhabitants, these compounds promote the growth of algae and cyanobacteria which can make your tank unsightly to look at. When water nitrate levels continue to increase, it can threaten the entire aquarium system, resulting in lowered pH and loss of buffering capacity, eventually leading to a pH crash which is very lethal to fish.

When you add new fish to a tank that has not undergone regular water changes, it can cause shock to the new inhabitants, causing them to succumb to weakness and disease.

Water change is different from “topping off” the aquarium. The latter simply involves adding water to a tank to replace the water that has been lost due to evaporation.

Tanks with larger fish or contain fish species that produce a lot of waste, like goldfish, need more frequent water changes to be performed. This involves more amount of water to be removed and replaced. Discus and other sensitive fish species thrive well under very low nitrate levels, and thus need frequent water changes, but with only a small percentage of water changed each time.

Other Beneficial Effects of Water Changes
Apart from removing undesirable components from the tank, water changes replenish lost carbonate ions or water buffers to promote pH stability while creating a healthy environment for the tank inhabitants. The process also helps replace important minerals and other trace elements.

Regular water changes can also help save money because it can render the use of carbon filtration completely unnecessary.

Water changes also have a great impact on the stocking of your tank. Studies have shown that water quality exerts a greater influence on the growth of aquarium fish than tank volume.

When problems arise, you may find that a water change alone is frequently all that is needed to fix them. Water changes may be considered the “prevent and fix all formula” for almost all the problems that an aquarist may encounter. A regular water change can prevent a host of problems that you might otherwise experience.

After a water change, you may need to leave the lights off for an hour or so, especially if you have sensitive fish, to let them relax. Make sure to double check your tank’s water chemistry a few hours after the tank has been cycled through a couple of times.

About the Author:
Peter Hartono is the founder and CEO of Just Aquatic - a proud Australian company that offers homegrown aquatic plants and aquarium supplies carrying top of the line brands including API, biOrb and Exo Terra. To find out more of our exciting offers and promotions check out our Facebook Page and follow us on Twitter at @justaquatic.

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