Why cant DIY C02 be done for a 72 gallon?

M

Mooch28

AC Members
Dec 24, 2004
809
0
0
Toronto (Brampton)
Ok,

simple queston, why? Blinky here is doing it for a 65 gallon planted aquarium, and its going quite well. Ive read so many places that you shouldnt use DIY C02 for a aquarium above 55 gallons, but no where does it explain why. The reason i ask is because i got a great deal on a Power compact lighting system today, which will give me 2.7 watts per gallon. By the way, will C02 Injection truely be necessaary at 2.7 watts per gallon as im still in the middle range for lighting?

Anyone got answers?

Thanks again......
 
In general, once you get above 55g, you have to make 2 or even more bottles of the yeast. All those cups of sugar will soon add up. The point of DIY is to try and reduce costs.

I.e. for my 90g to maintain a decent level amount of CO2, I'd need somewhere in the area of 3-4 (2L) bottles of DIY CO2.
 
I'm doing DIY on my 75g with 160W. About 15g of that is in the back filter that's not lit, so I consider it 2.7 wt/g. I've had my plants going for about a month with first 1 and now 2 2L bottles going. I'm still tweaking it a bit, but I'm planning on running at least 3 bottles. With more bottles, apart from more CO2, the rate is more constant, being less effected by the rise and drop of each bottle over its ~2 wk period. I can get huge bags of sugar at Costco, so the cost of sugar isn't much. If you want really luxuriant growth, I'd probably go with pressurized, but my Vallis is spreading runners like wildfire and I just like the idea of growing my "microaquariums" of yeast.
 
Mooch, it's not written in stone anywhere that you must have CO2 injection of any type when increasing your wattage. Using it just makes it easier.
Here's why: Plants use nutrients present in the tank whether they occur naturally from fish waste or you dose them. So does algae. Plants are a higher order of vegetation so they have a higher ability to use nutrients than algae, but they must grow well in order to do so. Since it doesn't take nearly as much excess nutrients to grow algae as it does plants, you want the plants to be growing at peak level so that they can use the available food in the tank. This is what many people call 'out-competing' the algae for the nutrients.
Carbon is one of the basic building blocks for your plants. When it is readily available it pushes the plants to use other available nutrients which gives them a greater ability to 'out-compete' the algae. Carbon is what you are supplying when you inject CO2.
The optimum level of CO2 in a planted tank with other inhabitants as well as the plants is 30ppm. The larger the volume of water, the more gas concentration is needed in order to achieve that level. DIY CO2 becomes an impractical option in larger tanks because the typical yeast/sugar method is inadequate for pushing the necessary quantity to reach the objective or 30ppm without using multiple bottles or much larger bottles, in larger tanks.
My estimation is that in a 72 gal. tank, with two 2ltr. bottles you would have difficulty consistently pushing enough gas to reach a level of 15 ppm. This will make things difficult for you in the battle with various algae. Of course that is just my estimate, but I don't think I'd be far off.
When I was using DIY on my 55gals. I was linking three 2ltr. bottles together and using a pretty decent reactor to achieve 22-24ppm. I was changing off one bottle every week to keep the mixtures fresh. This got old very quickly, especially for me because I had two 55s and was running three bottles over each of them. I also had other tanks using DIY at the same time. Seemed like I was spending all my time mixing yeast and sugar. It's not so much the expense, but the time involved.
It can be done in your tank, but will require large quantities of solution to maintain only fair levels, IMO.
Having said all that, I think that with your light level if you want to go the DIY route you can do it by planting very, very heavily. But count on a lot of work in order to keep your mixtures fresh to attain your goal.
I hope all this is a step towards answering your question.

Len
 
djlen said:
Mooch, it's not written in stone anywhere that you must have CO2 injection of any type when increasing your wattage. Using it just makes it easier.
Here's why: Plants use nutrients present in the tank whether they occur naturally from fish waste or you dose them. So does algae. Plants are a higher order of vegetation so they have a higher ability to use nutrients than algae, but they must grow well in order to do so. Since it doesn't take nearly as much excess nutrients to grow algae as it does plants, you want the plants to be growing at peak level so that they can use the available food in the tank. This is what many people call 'out-competing' the algae for the nutrients.
Carbon is one of the basic building blocks for your plants. When it is readily available it pushes the plants to use other available nutrients which gives them a greater ability to 'out-compete' the algae. Carbon is what you are supplying when you inject CO2.
The optimum level of CO2 in a planted tank with other inhabitants as well as the plants is 30ppm. The larger the volume of water, the more gas concentration is needed in order to achieve that level. DIY CO2 becomes an impractical option in larger tanks because the typical yeast/sugar method is inadequate for pushing the necessary quantity to reach the objective or 30ppm without using multiple bottles or much larger bottles, in larger tanks.
My estimation is that in a 72 gal. tank, with two 2ltr. bottles you would have difficulty consistently pushing enough gas to reach a level of 15 ppm. This will make things difficult for you in the battle with various algae. Of course that is just my estimate, but I don't think I'd be far off.
When I was using DIY on my 55gals. I was linking three 2ltr. bottles together and using a pretty decent reactor to achieve 22-24ppm. I was changing off one bottle every week to keep the mixtures fresh. This got old very quickly, especially for me because I had two 55s and was running three bottles over each of them. I also had other tanks using DIY at the same time. Seemed like I was spending all my time mixing yeast and sugar. It's not so much the expense, but the time involved.
It can be done in your tank, but will require large quantities of solution to maintain only fair levels, IMO.
Having said all that, I think that with your light level if you want to go the DIY route you can do it by planting very, very heavily. But count on a lot of work in order to keep your mixtures fresh to attain your goal.
I hope all this is a step towards answering your question.

Len
Click to expand...


Thanks Len, and the rest of you guys as well.That was an excellent description and i really understanc better why C02 is so important.

Well anyways, i have a couple of water jugs which are around 18.9 litres or 5 gallons. Im sure a bottle that size with the right mix would allow me to reach the 15-20 ppm mark, but any idea how long it wold last? Cost isnt an issue, because as the poster above said sugar can be bought in very large at cheap quantities at costco. If i could atleast 2-3 weeks out of a bottle this size, id do it, but if only a week.....its just too time consuming. Also any idea fo the ratio of sugar to yeast i would need for a 5 US gallon jug?
 
Mooch,
Just some thoughts through my experience in the last few months.
My goal was to find out how beneficial CO2 would be before I invested in a pressurized set-up. on my 115 it took 4-6 bottles to get the Co2 up to 19 ppm, and I had virtually 100% diffusion (no bubbles reaching the top of the tank) it made a world of difference with plant growth.
DIY Co2 I found to be a complete and absolute pain at this level. monitoring levels, changing and mixing bottles and making sure I had no leaks in the system was a constant hassle and battle. Not to mention spilled sugar, yeast, Fluctuating output, and limits on control. I learned what I wanted to know and now am sitting quite contentedly with pressurized Co2 on all three of my tanks. If I had it to do over, I would definately reccomend the pressurized system first, and if you don't like the results, sell it on the boards to recover some of your money.

That being said, Cost is the only issue that would ever put me back into DIY co2. And honestly as mentioned, the amount of sugar yeast etc. you use on a big tank will add up much quicker than for those doing CO2 on their 10g's.

Just my personal experience and hindsight.
Dave
 
I started with DIY to get the hang of things. I use a lot of mix to get the CO2 levels where I'd like them, and replace bottles weekly so there's very little fluctuation in the level of CO2. My husband is constantly wrinkling his nose at the smell of open 2L bottles left on the counter to start fermenting overnight, and making the mix for seven bottles is a lot of work. True, it can be done, but it is a bit time consuming, and several people have asked why I keep so much sugar in the house! I have been seriously considering pressurized for a while now (just spoke to my husband about it yesterday actually) to avoid the hassle. Changing 2 bottles on my 10g would be enough work, doing both tanks turns my house into a micro brewery every week :)
 
Thanks again guys, but while im at it....what the cheapest C02 injection system available on the net for a 72 gallon?

Id prefer a canadian vendor, since im in canada, but if cheap enough id consider buying via mail order, etc....
 
Also found this.......

For 87 US dollars, you get........

JBJ CO2 Regulator JBJ

Dual gauges..one for CO2 pressure and content meter
Solid Copper construction
CO2 Output line..silicone line connection
Needle Valve for precision adjustments
Superior quality German Solenoid
Light Indicator for on-off cycles
NOW INCLUDES BUBBLE COUNTER & CHECK VALVE
AC Power wire

All i need is a C02 tank and im ready to go right?

heres the link: http://www.co2-cylinder.com/en-us/dept_32.html Its the first item on the page listed at 87 dollars. This seems too cheap to be true...
 
You must log in or register to reply here.
AquariaCentral.com
Top Bottom