DIY CO2, bubbles not forming in bottle

[Edub]

Originally Posted by m00se

Put your sugar in your pop bottle. Fill the pop bottle with the warmest temp the yeast will tolerate (110 F). Shake to dissolve the sugar completely. Pour a small amount of that mixture into a cup (preferably pre-warmed but if it's thin walled plastic like a measuring cup I would skip this step). Sprinkle your yeast into this liquid and give it a gentle stir. WAIT UNTIL THE YEAST IS FOAMING. 10-15 minutes usually. Then add this mixture back into your main bottle. Add your pinch of baking soda now if you want to. Seal and go.

This. Treat the yeast like you would if you're baking bread. It really helps to proof it first because it starts bubbling faster and you can double check that your yeast is alive.

[DarkCobra]

1) Bottle caps are made of polyethylene, which (without some exotic techniques) cannot be glued. If it's not leaking now, it WILL leak later! The simplest way to get a reliable and long-lasting tubing connection is to drill a hole slightly smaller than the tubing, cut the tubing at an angle, and pull it through. However, your existing cap can be salvaged. Remove all glue, push the tubing through the hole, and shove a tubing coupler (or similar, like a plastic part from an airstone) from the inside of the cap into the tubing, expanding it into a snug fit.

2) The only time I've ever tried 1/4 tsp. of yeast, it failed to produce CO2. Sugar water does not provide all necessary nutrients for life. Yeast live in it only by recycling a limited nutrient supply from their own dead in an endless loop - that's why the max population (and CO2 production) tops out at an amount determined by how much yeast you add, rather than constantly increasing until the sugar is gone. With such a small amount of yeast, the nutrients may just be too sparse and diluted, leading to a "stall". You might try adding more yeast.

3) I use Fleishmann's "Active Dry" and lukewarm (body temperature) water. Only two failures - one described above, one when I skipped shaking the bottle. Anything fancier, including use of Prime or "proofing" the yeast, has proven completely unnecessary; although addition of 1 tsp. of baking soda does seem to extend production time slightly.

4) In a 2L bottle, bread yeast will die of alcohol poisoning before they can convert 2 cups of sugar. They're good for 1.25 cups guaranteed, 1.5 cups at best. Anything more is wasted sugar.

[kaaayd]

This is what I do and it works perfect every time.

Put some duct tape around the top of the bottle cap making something like a bowl. Fill it with gorilla glue and let it dry (with your tube through the cap of course). The best bottles for me are Gatorade. I've had issues with soda bottle caps leaking air out of the sides. Gatorade seems to make a solid seal.

[kaaayd]

Maybe should have read more lol... probably bad yeast.