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There are four main ingredients needed for the efficient productions of fish. They are dissolved oxygen, good water quality, good feed and good fingerlings. As important as all of these are however, the dissolved oxygen supply is the most important.

Poor water quality will slow down fish growth or can even kill in time. Poor fingerlings and feed will definitely slow down production. However, insufficient oxygen levels are guaranteed to kill the entire crop. Every one understands that if any animal does not get enough oxygen they are going to die. This is a fundamental fact of life. Few fish farmers recognize another factor with oxygen levels in a fish culture systems. A high level of dissolved oxygen for the particular species can also be detrimental to the animals health, not to mention to the owners pocket book as he has to pay for this.

Computerized 02 Station from Global Aquatics, Ltd.

To understand why high levels can be harmful, one only needs to think about the two factors of respiration learned high school biology, "Inhale" and "Exhale". Although many different species of fish require different levels of dissolved oxygen, there is one thing that is similar to all of them. Their respiration rate per minute are about the same under the proper conditions. Although I have never counted the breaths per minute of a fish, for the sake of this explanation let's assume that they take about 50 breaths per minute. A Tilapia is designed by nature to live in very poor water conditions being able to withstand dissolved oxygen levels as low as 2 ppm (parts per million). It would be very unusual in the tilapia's natural world for him to find water that had dissolved oxygen levels much higher than 4pmm and probably never higher than 6pmm. Since his system is designed to survive at this levels, he will only needs to inhale 50 times per minute to get enough oxygen and of course each inhalation is followed by an exhale which removes the CO2 from his body. Now, let's place this animal in water that contains two times as much dissolved oxygen, 8 pmm. This means that the animal only needs to breath 25 times per minute to get the required amount of oxygen. On the surface the response could be "So what? He is getting enough oxygen isn't he?" The answer to that is "Yes", but, he is also holding the waste gases in his system too long because he has cut his exhaling in half too. This can cause a fish to become ill.

The point to all of this is simple. In order to get good growth results from a fish system the oxygen levels must be held within certain parameters. Both high and low levels must be controlled. The computerized oxygen injection systems developed by Global Aquatics do just that. As a result, not only do the fish live in a comfortable environment, the extra cost of supplying more than is needed is eliminated.

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