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Water testing - what to look for

© Winston Vaughan Schoenfeld

In this article I will try and provide some information about water testing. Other than the apparent health of the inhabitants of your aquarium, water testing can give you a good idea of the quality of the water, and also help you detect potential problems that may eventually lead to disaster. Before I begin, let me first address the issue of water changes. Regardless of the type of aquarium you have, I recommend that you consider doing water changes every two to three weeks. During each water change, it is a good idea to remove about 15% of the water. Doing so will help ensure that you have a healthy aquarium, and should be adequate to maintain healthy levels of bacteria in your aquarium. Below I will list several types of water tests that you should consider doing to keep an eye on your aquarium. I have listed the water test types in two separate section. The first contains test for all aquariums, and the second if for only saltwater and reef aquariums.

All Aquariums

Nitrate - I have not listed ammonia and nitrate in the list here, but I have included nitrate. As those of you out there who understand the nitrogen cycle of aquariums know, ammonia and nitrite are common in new aquariums that are being set up for the first time. Assuming that your aquarium is already established, ammonia and nitrite levels should be at zero. Nitrate is a final product of the nitrogen cycle, and as a result accumulates in all aquariums over time. One exception to this is in well maintained reef systems. Nitrate can be consumed in reef aquariums, however in all cases nitrate levels should be kept below about 10 PPM. Slightly higher levels are tolerable in non-reef aquariums, but I still recommend that you try and keep levels not much higher than 10 PPM. Nitrate levels can be easily reduced by water changes. If you find that the typical 15% water change every two weeks is not sufficient to keep nitrate levels below 10 PPM, you should consider increasing the volume of the water changes.

Oxygen - I do not personally check the oxygen level in my aquariums since I am fairly confident about the filtration and aeration of my systems. There are cases in which you should consider testing for oxygen content. For example, if you notice that the fish in your aquarium are breathing more rapidly than usual, or they are constantly skimming the surface, this may be an indication that there is insufficient oxygenation in the water. For this type of water test, I recommend that you only check it as necessary.

The copyright of the article Water testing - what to look for in Aquariums is owned by Winston Vaughan Schoenfeld. Permission to republish Water testing - what to look for in print or online must be granted by the author in writing.