"Aquario Neo Co2 Diffuser Original The Neo diffuser from Aquario features microscopically small holes resulting in very fine and thorough bubble diffusion. The microbubbles produced allow for better Co2 dissolution in your water column, effectively allowing aquatic plants to absorb Co2 properly. Sleek and sturdy, the Neo Diffuser is made from transparent acrylic and is not easily broken when performing aquarium maintenance. Similar to other diffusers, users are able to place it in the corner of a planted aquarium securely with the provided suction cup. Product Features: Built-in bubble counter Reduction of back-flow pressure Smaller bubble than existing products Shatterproof construction, PC (poly-carbonate) pipe Available in 3 sizes Small Up to 20 gallons Medium 20-40 gallons Large 40+ gallons"