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CO2 Problems & Questions

2038 Views 3 Replies 4 Participants Last post by  anonapersona
I set up a 2 liter DIY bottle w/2cups sugar, 1/2tsp yeast, warm water to the bottle curve, shake to get it started. Well after a week the production was putting out a bubble per 2secs into my Hagen ladder. Right where the bubble comes out of the airline and along the very bottom ladder rung is this white ghost-like substance that seems to build up worse and worse each day until it clogs the bubbles in the lower rung. They have to build up to a massive bubble before it can push past this substance. The airline tubing from the top of th eladder to the bottom is also very white inside, but above the ladder down to the DIY bottle is clear still, some of the clear tubing is submerged in the tank along with the white part. What is this and how in the heck can I stop it as I don't feel I should be having to rip the CO2 ladder out of my tank daily to scrub this gunk off.

My second problem is the DIY stopped putting out consistently after a week of production, so like an idiot I shook it up a bit, then read later that that basically kills off the yeast. After I did that I would get no bubbles for several minutes then it'd spit out 7-10 rapidly then stop again and repeat several minutes later. I figured this is the product of kill the yeast, etc. So I made up a new batch using the same formula above and now several hours later the bubbles still only come out 7-10 at a time rapidly then stop for minutes... Any clue why these 2 things are happening and how to set everything up right?

Your knowledgeable help would be most appreciated. Thanks!
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I use 3/4 cup of sugar and 1/4 tsp yeast in a 2 liter bottle. That usually lasts for about two weeks. Since you are using more yeast and sugar that explains why it isnt lasting very long. I dont know what the buildup could be...maybe some sort of sugar residue is working its way in there. Try using less sugar and see what happens.
"TAG" is an aquatic flora magazine that is very much dedicated to the whole aquatic plant keeping hobby. In its recent issue, there was a very well-written article on DIY CO2 setup; specifically the 'Nyberg Method' It talked about how yeast cannot thrive on the sugar alone; it will kill them. Scientifically speaking, they require other nutrients to grow and survive; the likes of protein powder, for instance.

I tried the recipe it suggested, and so far so good. The result has been very satisfactory. Bubbles are constant and steady, and it's been going for more than 2 weeks. Basically, add 1cup sugar, instead of usual 2, for a typical 2 lit bottle. Some small amount of yeast, preferably wine types; something about their more rigid cell wall enabling them to survive longer than bread ones. Some sort of protein mix; yeast's nutrition. I use soy poweder; very cheap and easy to find. Can top with molass and baking soda; again, in fine amount. Once everything is set, this mix should keep you going for at least 3 weeks with fairly consistent CO2 production. When near the end of the cycle, save a small amount to start the next cycle. Your yeast will happily produce CO2 in no time, instead of the usual hour-long waiting. Again, I'm no science guy so whatever loop holes any science-inclined people want to fill in feel free to.

BTW, I like the glass ceramic diffuser more than the diffuser ladder.

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Yeast snot

That build up is from the yeast, it is common in DIY set-ups that do not have a bubble counter where the gas passes though water. The bubble counter scrubs the yeast out of the gas.

If you feel the need to shake the bottle to mix the sugar, you might try using a different cap, then connecting the cap with the line attached so you dont' get yeast mix in the line. Personally, I never shake the bottle when I use plain sugar.

There is also a gelatine recipe that I've used for a long time that has much less sugar and lasts a long time. You'll need Knox gelatine (comes in a box of 4 packets or a larger box of many packets) plus sugar and any sort of yeast, I've tried wine or bread yeast, not too much difference really.

On the box of Knox it has a recipe for Knox Blocks, follow that but substitute 3 cups water with 2 cups sugar for the 3 cups of juice it calls for. Make the gelatine, chill in a (brownie size -- 8"x8") pan overnight and then cut into cubes that fit into your bottle.

I use 1/3 to 1/4 of a pan of cubes and put the rest in a container in the refridgerator for next time. Add water as normal, to maybe 4" from the top of the bottle, and 1/4 to 1/2 teaspoon yeast. Best to let the cubes get nearer room temp, but sometimes I just put them in cold. Best to use barely warm tap water, but if the cubes are cold I use water a bit warmer, not at all hot though. Best to "proof" the yeast, adding it to warmish water with a pinch of sugar to hydrate and activate it before adding to the bottle, but sometimes I don't bother, just gently swish it as I walk from the kitchen to the tank.

If you follow "best practices" it should be making gas in 10 minutes or 20. Be sure no water is in the line as that is hard to work against.

Always set the bottle on top of the tank and be sure it is making gas before you put it below the tank, and be sure no water is in the line when you do put it down below.

Last, you may be developing a leak. Subemrge the bottel in a bucket of water for long enough to be sure if that is the case. I found aquarium silicon was not good, nor was hot glue. I now use Liquid Nails (found in the garage and at Home Depot in caulk section) on the top of the lid -- it will seal even with a unit in use and under pressure! Just peel off the old stuff, clean with alcohol and apply a lot.
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