DIY CO2 help needed

[Wackinator]

I've been trying to search up for a 20 gallon recipe online but people cant seem to agree on a specific recipe, some say go with 591mL bottle, others say 1L, and some say 2L.

Its my first time doing CO2 so I am extremely confused, I've read that fish will die within an hour or so if its too strong and I definitely dont want that.

Can someone tell me the perfect recipe to use? or something that works for them and please mention how long it lasts as well.

I have 591 mL and 2L bottles so which one is better?

I am also planning to diffuse them using a DIY co2 diffusing bell.

Hoping people can reply within a couple of hours as I want to have the mixture by the evening and let it stable till tmr morning then put it in the tank.

Its not densely planted yet though I hope they fill in nicely.

Thanks guys

[Vallisneria]

I use a 4l juice jug for my 20g with an Elite mini filter used to disperse the co2. With DIY co2 I've never experienced problems due to high CO2.

The basic recipe for a 2l pop bottle is 2 cups sugar, fill with warm water until the neck of the bottle(where it starts to narrow, or 4" from the top), then add 1/4tsp of yeast. It should last around 2 weeks before the CO2 production starts to taper. For different sizes scale it up or down accordingly.

For my 4l jug I use 3-4 cups of sugar, fill to the neck with water, and 1/2 tsp yeast. This recipe last around 3 weeks.

I've also tried brewing yeast but having noticed any improvement over regular yeast. Both last about the same amount of time before the co2 production starts to taper off.

[Wackinator]

I use a 4l juice jug for my 20g with an Elite mini filter used to disperse the co2. With DIY co2 I've never experienced problems due to high CO2.

The basic recipe for a 2l pop bottle is 2 cups sugar, fill with warm water until the neck of the bottle(where it starts to narrow, or 4" from the top), then add 1/4tsp of yeast. It should last around 2 weeks before the CO2 production starts to taper. For different sizes scale it up or down accordingly.

For my 4l jug I use 3-4 cups of sugar, fill to the neck with water, and 1/2 tsp yeast. This recipe last around 3 weeks.

I've also tried brewing yeast but having noticed any improvement over regular yeast. Both last about the same amount of time before the co2 production starts to taper off.

Thanks a lot for your quick reply. I am going to start the CO2 mixture soon, I just finished with the diffusion bell, its not much but I think it ll do for a little while.

I should leave it out of the tank for a couple of hours right? Cuz Ive read that the CO2 peaks at that time and then it stabilizes?

Do you do that?

Thanks

[Vallisneria]

I should leave it out of the tank for a couple of hours right? Cuz Ive read that the CO2 peaks at that time and then it stabilizes?

Do you do that?

I just put it right into the tank and the CO2 starts bubbling in a few hours after the pressure in the bottle has built up.

If you use warm water the yeast will start growing pretty quick. The bottle needs to be kept oxygen free for co2 production, so you need to keep your airline tube under water right from the start if you want to get it bubbling.

I dont' really pay enough attention to worry about the co2 levels and fluctuations. I put my DIY bottle on the tank, let it do its thing and in a few weeks when it starts to taper off I replace the mixture. Fish are happy and the plants are growing, so it must be working

I might say be a bit more careful monitoring if you were using canister CO2 but DIY is pretty fool proof.

[Cgy_Betta_Guy]

the recipe I have used for a 2L bottle is 2 cups sugar, 1/2 tsp of yeast and 1 tsp of baking soda. The baking soda is not necessary but I think I read that it helps to activate the yeast a little quicker and to keep the foaming down a little. I usually mix up a bottle and leave it out of the tank overnight to allow the yeast to really get going so it builds up pressure quicker. Then I hook it up to a glass bubble diffuser and let it do its thing and replace it in about 3 weeks. I never removed it from the tank in the evenings or anything as I never noticed that the co2 levels produced from a DIY bottle would be enough to harm the fish in either of my 31G or 58G tanks. Not sure how different it would be for your 20G. If you are concerned get a CO2 drop checker which will give you a decent indication of CO2 levels in your tank but will involve creating a base kdh solution so that the color measurement is accurate.

[Wackinator]

I should leave it out of the tank for a couple of hours right? Cuz Ive read that the CO2 peaks at that time and then it stabilizes?

Do you do that?

I just put it right into the tank and the CO2 starts bubbling in a few hours after the pressure in the bottle has built up.

If you use warm water the yeast will start growing pretty quick. The bottle needs to be kept oxygen free for co2 production, so you need to keep your airline tube under water right from the start if you want to get it bubbling.

I dont' really pay enough attention to worry about the co2 levels and fluctuations. I put my DIY bottle on the tank, let it do its thing and in a few weeks when it starts to taper off I replace the mixture. Fish are happy and the plants are growing, so it must be working

I might say be a bit more careful monitoring if you were using canister CO2 but DIY is pretty fool proof.

the recipe I have used for a 2L bottle is 2 cups sugar, 1/2 tsp of yeast and 1 tsp of baking soda. The baking soda is not necessary but I think I read that it helps to activate the yeast a little quicker and to keep the foaming down a little. I usually mix up a bottle and leave it out of the tank overnight to allow the yeast to really get going so it builds up pressure quicker. Then I hook it up to a glass bubble diffuser and let it do its thing and replace it in about 3 weeks. I never removed it from the tank in the evenings or anything as I never noticed that the co2 levels produced from a DIY bottle would be enough to harm the fish in either of my 31G or 58G tanks. Not sure how different it would be for your 20G. If you are concerned get a CO2 drop checker which will give you a decent indication of CO2 levels in your tank but will involve creating a base kdh solution so that the color measurement is accurate.

Thanks guys, both for your replies, and your recipes seem similar and yeah Ive read that some people put Baking Soda but I couldnt find any lol.

Everything is set up and hopefully starts bubbling soon, any clue how long it takes for them to build up?

Maybe next time Ill try leaving it for a night to help with the pressure buildup.

Thanks

Edited March 7, 2010 by blackbelt609

[Kronosdelsol]

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Edited October 2, 2010 by Kronosdelsol

[Wackinator]

You should see it bubbling by the next day for sure. If you use 2 litres pop bottle, 2 cups of sugar and 1/4 tsp of yeast, it should last for at least 1 month. But mind you my tank is in the basement where it is cooler. If yours is on the main floor, it should last at least 3 weeks. Just keep an eye on the bubble counter or buy a CO2 drop checker for $10 on ebay.

yeah I think I messed this up somehow because the only time Ive noticed it bubbling is when I pick up the bottle and give it a good shake myself.

Oh well Ill try again in a couple of days and hope for a better result next time.

I might look into a bubble counter as its something a lot of people recommend apparently.

Thanks again

[Vallisneria]

If you aren't seeing bubbling after 12hrs or so then the yeast might be dead or the temp of the mixture might be too low. My tanks are in the basement and it can get pretty cold and it slows down the bubbling a lot. I now keep my DIY co2 bottle on my light fixture. The lights keep it warm and it bubbles like crazy.

[Wackinator]

If you aren't seeing bubbling after 12hrs or so then the yeast might be dead or the temp of the mixture might be too low. My tanks are in the basement and it can get pretty cold and it slows down the bubbling a lot. I now keep my DIY co2 bottle on my light fixture. The lights keep it warm and it bubbles like crazy.

Ill try once more tomorrow but I think its the yeast, it was probably dead or something.

Is there a way you can test it? It bubbles but only after I shake it.

Thanks

[jvision]

If it bubbles at all, then it's not dead yeast. You probably have a leak - when you make the hole in the bottle cap, make sure it's smaller than your airline. And make sure the cap is screwed on tight. If you want to know for sure if you have a leak, you can submerge the bottle and give it a squeeze with the hole plugged - if there are leaks, bubbles will come out of where it shouldn't.

[Kronosdelsol]

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Edited October 2, 2010 by Kronosdelsol

[Wackinator]

If it bubbles at all, then it's not dead yeast. You probably have a leak - when you make the hole in the bottle cap, make sure it's smaller than your airline. And make sure the cap is screwed on tight. If you want to know for sure if you have a leak, you can submerge the bottle and give it a squeeze with the hole plugged - if there are leaks, bubbles will come out of where it shouldn't.

Take a screw that is the same size as the inside diameter of your tubing, then drill a hole into the bottle cap. Cut a slit in the tube so that it has a really long diagonal point. Then use pliers to pull it through. you shouldn't need any silicone around the tube and it shouldn't leak.

Thanks guys, yeah I did have some issues making the hole in the lid so maybe Ill just make another lid cuz when I shake it it does bubble like crazy and another problem is I dont have a checkvalve, I didnt know where I would be able to find one as I dont even know what that is.

Thanks though

[Vallisneria]

Thanks guys, yeah I did have some issues making the hole in the lid so maybe Ill just make another lid cuz when I shake it it does bubble like crazy and another problem is I dont have a checkvalve, I didnt know where I would be able to find one as I dont even know what that is.

Thanks though

If you think the hole might be leaking put some silicon around the hole. Thats what I do to make sure it doesn't leak around the tubing.

A check valve is a little one way valve you put in the airline tubing. The co2 can flow through but the tank water can't flow back up the tubing, past the valve. You can buy them at pretty much any LFS, it should be around the airstones and tubing.

[Wackinator]

Thanks guys, yeah I did have some issues making the hole in the lid so maybe Ill just make another lid cuz when I shake it it does bubble like crazy and another problem is I dont have a checkvalve, I didnt know where I would be able to find one as I dont even know what that is.

Thanks though

If you think the hole might be leaking put some silicon around the hole. Thats what I do to make sure it doesn't leak around the tubing.

A check valve is a little one way valve you put in the airline tubing. The co2 can flow through but the tank water can't flow back up the tubing, past the valve. You can buy them at pretty much any LFS, it should be around the airstones and tubing.

yeah I will definetely look for a check valve the next time I go and since I dont have Silicone Ill try some of the sticky tac kinda thing i have laying around. Thank though

And I had one more question my airstone is growing all fuzzy and some sorta fluffy layer is forming around, what is it?

Ill try to post a picture of it by tonight but it did the same thing last time and I cleaned it off hoping it wouldnt show up again but it did.