use a bubble counter and you should be well on your way!

simple DIY bubble counter is a small bottle/jar half filled with clean water,take a tube from your 2-liter bottles and have the other end go through the lid of the bubble counter right down under water level
use a second tube from inside the jar above water level and take this to your tank

it cleans the co2 gass before entering your tank stopping alcahol and white residue from being a problem!


if this dont make sense i will try to find a picture!
hth robert.

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