Join Date: Sep 2003
Location: Somerdale, New Jersey USA
Pearling is really over-rated and the lack of it is does not mean that the fish will be starved for O2.
Pearling is a result of super O2 saturation in the water and requires close to optimum conditions to attain.
If you are not experiencing major algae issues in your relatively new tank, you are creating a balance in the tank and have no need to push the CO2 over what you are supplying, IMO.
Many people feel that CO2 ppm of between 15 and 20 is adequate to maintain good plant growth.
A major part of the equation that you are not mentioning is plant nutrition. Are you feeding them anything? You have close to 4 watts/gal. With that lighting, and CO2 injection, they will be in need of some supplemental feeding or will start to look a bit weak before long.
I suggest that you pick up Nitrate and Phosphate test kits, and test your tap water and tank water individually to see what your water's content is of these elements. These two plus Potassium are the macro nutrients that the plants need. In addition, they also should have some trace minerals in their diet.
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