Passive CO2 in Plastic Bottle

[Cal]

I recently saw a video of Cory visiting a store in San Francisco area. The owner was filling up an empty Gatorade bottle in the fish tank. Does anyone know how they are securing the bottle from flipping over? The video shows the owner going tank to tank filling up CO2 in an inverted plastic bottles with a piece of Styrofoam.

 

[Prince]

If you want some diy co2 kits I have a few of the Hagen systems with the ladders. The work great on small tanks like 20 gallons

 

[Cal]

It's way more basic than that. In the beginning of the video you can see the fish store owner filling up CO2 in an inverted plastic bottles.

 

[Becca]

I've heard of using a soda bottle with a yeast culture to make your own CO2, but this is new to me...

 

[Airborne001]

I used to use a one gallon lab bottle, with a yeast culture in it. I fed the line into the intake on a power head, to chew up the bubbles and dissolve them into the water stream.

That one culture was able to feed a 125 heavily planted tank.