DIY CO2 question???

[stina]

HI PPL!
One serius question... should i turn off my DIY CO2 system at night?
I am using it in my new 180l plannted tank, tank is running allmost two weeks now, and every thing looks good... glossastigma is starting to spread nicely...
I am using two PET bottles(1,5l & 1l with 0,5l filter bottle) filled with CO2 linked in a chain, and my difusor is in the middle of the tank...
I really don't know how much bubbles do i have per minute...
TIA
regards!!

 

[Terje]

Everything depends on your tank. Is it crowded? Are there many plants?

I've got a 160L planted, with DIY 1,5L CO2, and I never turn it of. My filter is keeping the surface moving, so the water get some O2 around the clock.

But if the fish is hanging in the surface every morning you'd might consider turn it off at night :wink:

 

[farm41]

I have pressurized co2, and I leave it on 24/7. No problem with it here.

What recipe do you follow?

 

[stina]

OK, my tank is Juwel rio 180, and my filter pumps straight in to the surface... so O2 is OK(i think )
I have biger bottle(1,5l) 1 little tea spoon of bakers yeast and 2x2dcl of sugar...and in smaller bottle(1l) i have 2dcl of sugar and small tea sopoon of yeast...bottles are conected...
I didn't turn off CO2 at night for the first few days, and then some PPL start to freighten me in my home forum... :?

 

[farm41]

OK,

that recipe may fluctuate quite a bit.

You should try:

2l bottle
1 cup sugar
1/8tsp yeast
1 tsp baking soda
water, fill to curve near top portion of bottle

this recipe, although slow starting, can give a steady output of co2 for 3-4 weeks. I always used 4 bottles on a 55 chained together and rotated one bottle weekly.

You could use 2-3 bottles on a 29, and rotate on 10-14 day intervals for the steadiest output.

hth

 

[stina]

Sorry farm41...i didn't understand all...

"You could use 2-3 bottles on a 29"
What on 29?? Do you mean Gallons? I have 180l tank, and that is cca40G of water...(20l is going on supstrate...)

Also, can you please explain how do you think i could control my CO2 fluctuates?

Also, what do i acomplish with bottle rotations??

Sorry, once again, my english sucks...
regards

 

[Terje]

Also, what do i acomplish with bottle rotations??

The first days, the yeast doesn´t produce a lot of Co2 but it produces more and more after each day. It also produces alcohol, and the alcohol eventually kills the yeast. This happens at an alcohollevel at around 14%
To make the Co2-levels in the tank more stabil you should rotate. When one bottle produce max Co2 the other one will be at a minimumand vice versa.

Yeast made for winemaking can handle a higher percent of alc. and make the bottles last longer.

 

[farm41]

Well, I don't know where I got the 29g from. :?

With the recipe I gave you though, you could easily use 3 bottles on your tank of 40g. The reason for rotation is for precisely the reasons that Terje states.

 

[LyreTail]

You should not turn off yeast CO2 because of the possibility of the bottle or connections exploding under increasing pressure

 

[Terje]

You can simply disconnect the hose. No need for blocking it.

 

[stina]

When i say "turning off the CO2" i mean just simply put out the difusor... so CO2 can simply go to air...
I will try with that recipe...aldo i didn't quite understand how come that all bottles don't have the same CO2 inside them if they are linked...??? :?
Also, how can you know what is the right CO2 concentration for my tank??
I know i trouble you to much, but i need some sci info..?
I don't want to offend someone, but i would like to share my knowledge with my friends, and i can't just say to them "it is like that!"
TIA, hope you have understood me... :wink:

 

[farm41]

Also, how can you know what is the right CO2 concentration for my tank??
I know i trouble you to much, but i need some sci info..?
I don't want to offend someone, but i would like to share my knowledge with my friends, and i can't just say to them "it is like that!"

I don't know what the concentration will be, but with the experience of having had 4 bottles on my 55g and 2 on a 20g, I would be very certain that it would not be too much.

Then you would need to test it, to verify that co2 is somewhere in the beneficial zone.

http://www.thekrib.com/Plants/CO2/kh-ph-co2-chart.html

 

[Terje]

...aldo i didn't quite understand how come that all bottles don't have the same CO2 inside them if they are linked...??? :?

It's not the kind of CO2, but the amount of CO2 each bottle produce.
When one of the bottles produce at lot of CO2 the other one will produce little.
Does it make any more sense?

 

[stina]

Yes Terje, now it does...thank you!
I am having some discussions wih my friends( 2 of them are veterinariens...specialization - fish), and they are havin their own theory and you know how it goes... to much info, and everybody has their own idea!
I will study that link you have gaved me...
If i will have any other questions, i know who i will molester once again...
Thanx guys!!
regards

 

[stina]

Ok, one more question, it is the same, but i need your help!
If CO2 bottles are in serial connection, they each have same amount of CO2, right?
And the last bottle have by some reasons maximum CO2 output, and that bottle can couse CO2 fluctuations, so that is the main reason why I must rotate bottles every 10-14 days??
Is this correct?

Terje, i have now realised, that you have misunderstood my previus question...I didn't ask about "kind" of CO2...

Thank you once again
regards

 

[aspen]

actually ALL of the bottles would be making co2, some more than others, depending on whether they are new or not. you are alternating them to level out production.

rick

 

[Christine-FishGrrl]

I have a 25 gallon long tank that I have two 2-liter bottles of DIY CO2. I rotate the bottles by which day I make a new batch - one bottle gets done at the first of the month and the other in the middle of the month. That way I keep a fairly steady amount of CO2 in the tank.

This is the recipe that I use that will easily last 4-6 weeks:

2 cups granulated sugar
1/4 tsp baking soda (helps to buffer the solution)
1/8 tsp of Champagne yeast
warmish water

If you use baking yeast (Fleischman's, Red Star, or other kinds at supermarket) they will only last 10-14 days. This type of yeast cannot tolerate acid environments or alcohol and dies very quickly. Baking yeast also has the problem of giving off a LOT of CO2 very early and then quickly dropping off, so even after a couple days you don't get that much CO2. Finally, Baking yeast is a top flocculate (spelling?) meaning you get lots and lots of foam on the top and if you fill the bottle too high the gunk goes into your tank.

Champagne yeast is perfect for acidic, alcohol-filled solutions and it has a slower and steady rate of CO2 production. It is a bottom flocculate so there's less danger of stuff getting into your tank. You can find Champagne yeast at any local brewery supply or by mail order. It is more expensive but you use less of it for each batch and it lasts twice as long. Keep it in the freezer.

You never have to worry about turning off your CO2 at night as long as you have enough O2 in the water (which you should have if your plants are photosynthesizing enough - "pearling") and enough buffering capacity that you don't have pH crash. CO2 and O2 are independant of each other - having one doesn't crowd the other out, water can have plenty of both. If your fish are gasping for O2 in the morning, it isn't the fault of the CO2 it means you need to get more O2 in the water by adding more circulation or getting the plants to photosynthesize more.