Plants need light and food to grow, but did you know that they also need CO2 or carbon dioxide? Aquarium owners who stock live plants will find that the addition of carbon dioxide to their tank will help fuel the growth of their live freshwater plants.
Adding carbon dioxide to your fish tank produces some highly noticeable effects immediately. It's like giving them a boost of energy, which helps them grow.
Depending on your goals for the planted tank, there are many carbon dioxide systems choose from. If you're just starting out you could make a do-it-yourself system, or buy a fairly inexpensive one. Serious growers of live aquarium plants could spend up to $150 or more for a powered system. Higher-end systems include a CO2 tank, dual gauge CO2 regulator, needle valve, silicone air line tubing, and the CO2 reactor. Here's an example of a higher end set up.
The optimum level of CO2 in your aquarium should be between 5 to 15ppm (parts per million). You can best determine this with a CO2 testing kit. Too much carbon dioxide in the tank could be harmful to your fish since they intake oxygen like humans.
So if you want to give those aquatic plants of yours that extra boost of growth, consider adding carbon dioxide to your aquarium. Just be warned, you may be doing a lot more clipping soon!