Originally Posted by JulieJules
Thanks everyone! One more question!
In your experience, which works better with plants? Flourish Excel or Flourish Comprehensive?
Two totally different items. Flourish comp is a fertilizer. Flourish Excel is glutaraldehyde, about a 1.8% solution. It's a chemical carbon supplement, NOT a fertilizer. You want to use Flourish comp.
I make my own Glut solution and it grows plants up to 4x normal, dosed daily in a fish tank. It works well. Honestly though, pressurized CO2 gives much better results (up to 200x increased growth rates(!) - without the dangers of working with Glut. Glutaraldehyde is a pretty nasty respiratory and skin irritant. It's actually an agent used to chemically disinfect equipment.
For more background, plants need nutrients (the flourish comprehensive and root tabs), light, and a carbon source to grow. Excel increases biologically available carbon. Pressurized CO2 also increases the carbon availability. That being said, you do not need to use either one, plants will grow well, just more slowly (normally).