Buy a Mini Gravel Filter , pull off the hose and plug that end with a standard Air Tubing Plug . .Now cut a piece of tubing to run from the inside of the Stack Head to 1" from the end of the tube. I placed a tee on the end to airline , if for no other purpose...it looked good there ! Anyways... Now just run your Air Tubing through the Stack Head with a tubing connector . Off the other side of the connector attach your tubing to the CO2 supply ... Simple as that.

The larger the bubble inside your diffuser, the more CO2 enters into the water column. When positioning the diffuser remember that water flow past the throat of the diffuser will increase water volume contacting your bubble. I have a powerhead in the corner of tank that points down to diffuser and puts constant flow past the opening. I keep a heavily stocked tank in regards to fish so water flow is critical to me anyhow. Any excess buildup of CO2 in diffuser will just release to surface and dissipate. At 1 bubble every 5 seconds I have 1 large bubble escaping the diffuser every few minutes. When my CO2 Generator slows to 1 Bubble every 10 seconds it still will still release CO2 and maintain a large " puddle " of CO2 dissolving into water at all times. You will be able to tell easily when a new yeast mix is needed because your Mix will not be able to keep up with the dissolving "puddle" in the tube .

Another good feature of this set-up is that it acts as a nice " Bubble Counter " as well. Now you can monitor your Yeast Mix without trouble. You will never need to guess again if your generator is producing CO2 at a good rate and you also can eliminate having a seperate counter hooked up.

Notice the angle in the END VIEW . This angle is what determines the overall size of the CO2 puddle by holding back a " thicker " bubble. It isnt the thickness of the bubble that will gain you CO2 content in your water but the " Surface Area " of the bubble to water contact that counts. If it is adjusted so that the bubble is at the center of the tube and the tube is level it will have the greatest amount of CO2 in contact with the water for dissolving. For a lesser amount of CO2 simply angle the tube position to give you a smaller amount of bubble contact with water. Excess CO2 will simply rise to surface leaving a constant size of bubble contact as you can see in the SIDE VIEW photo.

After it is installed be sure to test the waters PH ! All those articles on the how-to's of water parameters are out there and I strongly suggest you Read .. Read .. Read ... like I said this setup is in a 30 gallon and my plants were flowing 02 and were noticably happier in the first day ! This setup "might" work in a larger tank if your demands for CO2 are light but I wouldnt depend on it.

If you have been an " Aquarium Accessory Pack Rat " like me over the years you probably have most of the parts allready... and the mini-vac ?? I paid 3.99 for that. Have fun with it and if you have any suggestions or ideas to improve on it I would be interested to hear them . Enjoy !