Join Date: Oct 2007
Location: Ontario, Canada
I think if you go Excel, might as well combine it with DIY CO2 to get maximum results.
Or else you can:
1. Blow air through a straw a couple of minutes a day into the water, you can get up to 10 ppm in about 10 minutes in a small tank I think.
2. Have tons of water to air movement and churning, so even though the CO2 levels are really low, it'll constantly be replenished as quickly as your plants use it up. <-- it should work theorectically, but I could be wrong.
CO2 is very important! Excel is just not real CO2 but a substitute... a very expensive substitute that is. But it does work effectively.
So what works best is either DIY CO2, or DIY CO2 + excel.