No Silicone DIY Yeast CO2 Reactor and Diffuser for Planted Aquariums




Introduction: No Silicone DIY Yeast CO2 Reactor and Diffuser for Planted Aquariums

After having to re-do the silicone on so many jars because the CO2 un-glued the silicone from the bottles, I needed a new way that provided me with CO2 for my aquariums but no need to constantly be checking if the silicone was the reason I am not getting as many bubbles.

My husband kept complaining about the initial smell of the raw aquarium silicone sealant and to be truthful I hate that smell. I knew I could not spend too much money, so with the help of the internet and inspiration from home brewing sites I got this idea and it cost me less than $10: I got a rubber stopper and a bottle and got to making. Let me show you...

P.S: I have done this now with two of tanks, 1 with the 1 gallon jug described in this tutorial and one with a 3 gallon polycarbonate bottle for my 45 gallon tank, if 3 gallon yeast CO2 has not blown the stopper off, I don't know what will.

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Step 1: Step 1: Materials

I made this one for my 20Gallon long, and since I did not want multiple bottles I used a 1 gallon jug

You will need:

  1. 1 gallon Jug of strong plastic. I used a clean vinegar jug (FREE)
  2. Several feet of airline tubing ($3 at home depot)
  3. Check valve (FREE I used one I had but these cost cents)

  4. a drill with a 1/4" bit (FREE if you don't have a drill use a VERY SHARP KNIFE)

  5. scissors

  6. a bamboo reed (dried bamboo reed) (FREE from a park's bamboo tree)

  7. A black rubber stopper ($4 at home depot)

Step 2: Step Two: Prep

  1. Choose your bottle first.
  • I like harder plastic as it does not tend to expand as much with the pressure of the CO2.
  1. Get the rubber stopper. It must fit VERY VERY TIGHTLY so make sure that it does not go all the way in)
    • Take the bottle you have chosen to your hardware store and buy the rubber stopper that fits your bottle. (Not all bottles are the same so by taking the bottle along you will make sure that your stopper fits TIGHTLY) for my bottle I used a 1 11/16"
  2. Cut your line
    • Cut the line a little longer than you think you will need from where you will place your bottle to the bottom of your substrate

Step 3: Step 3: Assemble the DIY Diffuser

  1. Choose the piece of bamboo reed you want to use as a diffuser.
    • Test the reed in a cup of water to gauge bubble size. I have these in every one of my tanks and they produce supper fine bubbles.
    • Take your time with this step. This will take some try and error as not all reeds will produce small bubbles, some will just make air stone size bubbles and that is not useful.
  2. Insert the reed into the end of the air line so air will only go out the reed and not the end of the tubing.
  3. Place the bamboo reed into the tank and measure out the tubing so it reachess the floor or where your reactor is going to sit and cut the line. Attach the OUTPUT side of the check valve.

Step 4: Step 4: Assemble Bottle

  1. Drill the middle of the rubber stopper with the 1/4" drill.
    • This hole will look very small, don't worry.
  2. With the remaining Air line tubing. Take the scissors and cut about 1" of one end of the air tubing in half and pass it through the rubber stopper
    • This will be very tight, so use pliers or your teeth to pull and your finger to push simultaneously until 1.5" (just passed the cut part) is through to the other end of the rubber stopper
  3. Mix your CO2 recipe and pour it in
    • Here is what I used for my 1 Gallon jug: 4 cups of white sugar, 2 tsp of baking soda, 1 tsp of yeast
  4. Push the rubber stopper until it does not go in anymore no matter what you do (the tighter the seal the better)
  5. Insert the end of the air line tubing into the INTAKE add the check valve. (the intake should already be into the line leading to the reed in your aquarium.
    • MAKE SURE THE AIR FLOW IS GOING THE RIGHT WAY. if you don't know which way, just blow into it and feel which way the air flows.

Step 5: Step 5: Watch the Tank

You are done, my recipe took about 1hr to begin good bubble count.

Now just watch and enjoy good CO2 without the messy hassle of aquarium silicone.

Thank you for reading!

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    3 Discussions


    5 years ago

    At "Yeast" you don't have to worry about redoing the seal again. 2/3rds of a pun is PU! Nice instructable :-)


    5 years ago on Introduction

    This is great! Awesome work. I'm excited to see more from you in the future!