DIY CO2 - what did I do wrong?

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I've been out all day, so haven't been able to come back to you.

If my gas seperator bottle continues to get water in it, I'm going to have to take it apart. It'll be full in another 24 hours.

Here's a pic of the setup.

co2.jpg


Don't worry about the second bottle. It's not hooked up. You should be able to make out the check valve just above the 2L bottle. The airline from that goes to the small bottle on the left. This is the one that's slowly filling with water. The water is dripping from the airline tube that is connected to the 2L bottle. Wierd!!

The yeast is Lowan Instant Dried Premium Bakers Yeast. It comes in a vacuum sealed tin with a resealable plastic cap. It's new and it's useby date is Jan 2010.

I don't see how the small bottle can be a bubble counter....
 
Hang on... I lie! I just had another good look and the water is coming from the airline that's attached to the diffuser in the tank! Water is dripping into the bubble counter and down the airline into the gas seperator... What the?!?! Surely I could not have been so dumb I put the bubble counter in upside down?!
 
The gas separator can be a bubble counter if you were to put a piece of rigid airline tubing on the bulkhead that comes from the mixture bottle, and fill the gas separator with water. Then, co2 will flow down the tube, bubble up in the water, and exit the other side up to the tank.

Even if you left it the way it is though, i would consider moving the check valve so it is closer to the top of the aquarium, and still fill the gas separator with water. This will be less volume you have to pressurize to get the co2 into the tank.

I gotta point out too - your mixture does not look good. It looks dead. When my mixes were active, they had a frothy head on them, and were very bubbly looking... very fizzy. Yours looks just like you said, ice tea or something. Maybe the particular kind of yeast you have isn't good for an anaerobic environment? Not sure. You could attempt to go to a wine making store or something similiar, and buy some specialized yeast. It really is a long shot though, I don't have a good explanation as to why the yeast in oz would be in different than our plain old bakers yeast. I don't like the idea of a resealable container though, the common stuff here comes in little small packets so it is only exposed to air/environment right when you open it.
 
Here is a pic of my old diy in action - you can see my gas separator/bubble counter setup as i described, and also, kind of hard to see, but see the foamy frothy head on the mix in the clear bottle?
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The location of your mix is probably part of the problem. Try putting it on a small table to get it off the ground so that the CO2 has less pressure to fight against.
 
problem solved. use granulated sugar (cane i think) its the white stuff
 
Not sure if that will solve the problem, but it may help. I have heard you can use any range of sugar substances though, from molasses, to grape jelly, etc.
 
i bet you!!! i say i'm right just by taste alone. brown sugar sucks i wouldnt eat it if i was yeast. regular sugar is way better.
 
I doubt the brown sugar is the issue (however I concur with your taste assessment!). Plenty of aussies use brown sugar in DIY setups. The rationale with using raw sugar is that it contains a mixture of simple and complex sugars with the complex sugars taking longer to be metabolised by the yeast.

So I am told anyway :)

But in other news, I've had a little success. I dunked the seperator bottle in a bucket of water and I found a very tiny leak. I have removed the gas separator from the setup so the airline from the bottle to the check valve and then the check valve is now connected to the bubble counter, then to the diffuser.

But I might still have an issue with the yeast. I'm not sure.

I also wondered if the water was too warm when I was activating the yeast, so last night I tried activating some yeast with cooler water (25 degrees C instead of 30). I put a little water in, added a pinch of sugar, gave it a good whisk it and waited 10 mins and it wasn't even frothing. There was no movement. I did this twice with the same result.

Late last night it was evident that the last mix wasn't working. I tried another way involving just adding the yesat straight into the bottle of tepid sugar water, ans shaking vigorously. After an hour the yeast was sitting at the top doing nothing. No movement. As of now, it looks flat and no bubbles that I can see. I left it o/night and all day today. BUT when I removed the seperator and I did notice the 2L bottle felt very firm indicating some pressure was there. I gave it a gentle swish (yes Deb I was extremely careful) and it fizzed a little.

I squeezed the bottle a bit and bubbles did go though the bubble counter. I waited a bit and squeezed again and for the first time I have CO2 coming from the diffuser.

Guess I'll wait more and see if I actually get bubbles though the bubble counter without me having to squeeze the bottle. But I dunno... this yeast just seems to be a little Not-Quite-Right.... Might go buy me some champagne yeast this weekend.
 
Yayyyy, things seem to have come together. I now have a bubble rate of 36 bubbles a minute (or 0.6 bubbles a second) and a fine mist is now eminating from the diffuser.

Hope that's not too much for a 15G.

Should I be gassing off the CO2 during lights-off-time with an airstone?
 
Sounds like it's really kicking now.

Some like to run an airstone during lights off hours to offgas it. Depends on what kind of fish you have in there I guess, and how high your CO2 level is getting at night.
 
I'm glad you were careful with the yeast :) IMO, your bubble rate isn't so high that you need to offgas at night. Watch and see how the fish are in the morning before you set up an airstone. I think they'll be fine.
 
6:50am - no dead fish or fish gasping for air at the top, just one human struggling to wake up.... All seems remarkably well!

I could still be sleeping tho. :)
 
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