FAQ: Is Seachem Flourish Excel™ a replacement for CO2 in a planted aquarium?

A: Yes and no. It provides the same benefit as CO₂, i.e. it provides the plants with a source of carbon for growth just as CO₂ provides them with carbon. However CO₂ by itself will give you quantitatively more growth than Flourish Excel™ by itself, although Flourish Excel™ does provide a substantial amount in comparison. If CO₂ is a 10, Flourish Excel™ is a 6-7. Using both together provides additional benefit. One of the advantages of the Flourish Excel™ is no up front equipment costs and complexity of valves, hoses and regulators, etc.