DIY CO2 System for Planted Aquarium
Georgia Aquarium | Explore the Aquarium | THE SMURFS 2 AMERICA THE BLUETIFUL
A very informative website about CO2 for plant nutrition. How to make a DIY CO2 unit, and how to properly diffuse it into the water.
DIY CO2 production: I use this myself, but I use another smaller 'filter' bottle with water where the CO2 needs to go through. Is also a bubble counter!