Co2

[fish_r_great]

I thought that I might want a Co2 unit but don't want to spend $200+ on a unit so I was wondering how to make a simple one. I know rain- makes hers.

 

[Lateral Line]

There is a very simple DIY CO2 system described here. My own is a little more sophisticated to allow for easier maintenance and a more even CO2 supply rate, but works in much the same way.

 

[fish_r_great]

Cool thx lateral line. If I did that where would i put the end of the tubing not attached to the bottle? By the intake of my peguin filter inside my tank or inside the filter housing?

 

[Lateral Line]

If the filter is a hang on the back type of thing, then you'll want the diffuser to be as far away from it as possible. The agitation that kind of filter creates will knock the CO2 out of solution before the plants get a look at it. CO2 comes out of solution very easily, you'll want to minimse surface agitation etc., to get real benefit from CO2 injection.

I have the outlet of my CO2 system run into the inlet of a canister filter group.

 

[fish_r_great]

Mine is by the intake of the hang-on-back "thingy" is this good or bad?

 

[superpenguin22]

Mine is by the intake of the hang-on-back "thingy" is this good or bad?

thats fine. What I do with my co2 system is i put the end of the hose in my penguin mini filter right behind the bio-wheel with the water flow so the co2 is diffused well.

 

[fishatron7429]

There is a very simple DIY CO2 system described here. My own is a little more sophisticated to allow for easier maintenance and a more even CO2 supply rate, but works in much the same way.

Hey Lateral Line I have this filter and i dont know what you mean by this quote from that discription you made
"Of course there are more but I dont want to get that detailed into the diffusion. If you are running a power filter just stick the tubing into the intake and the impellar will dissolve the C02 very well. Another easy method is an airstone, but let me tell you from my experience that it is a poor method and most of the C02 doesn't dissolve into the water. So I'd stick with the filter intake method it works great."

 

[ChrisH]

I am a little confused as to the best place to put the tube from my reactor into the tank. Should I put the pipe near the inlet to my filter, or into the tank via an airstone?

Many Thanks!

 

[Lateral Line]

There are 2 problems CO2 disolves fairly slowly, and once disolved comes out of solution again very easily.

If you bubble the CO2 through an airstone, most of it will simply escape at the surface. There are some devices called snails or spirals which make the bubbles go round and round before reaching the surface, other devices are like upturned cups which hold the CO2 under the water. What they are trying to overcome is the first problem - you need to keep the CO2 in contact with the water long enough for it to dissolve.

The second problem can be reduced by lowering the agitation in the tank. Gases exchange at the surface, and a lot of surface agitation gives the CO2 plenty of time to escape before the plants can use it. Thus biowheels and most HOB type filters are not a good places to add your CO2.

I use external canister filters with extra stages on them. The CO2 from my reactors goes into the inlet tube for the filter train, it then has the entire length of the filter system to dissolve, and I purposely arrange the rtank return to create minimal agitation by using more then the recomended number of return pipes, (slows the flow down), enlarging the holes, (reduces currents), and angling the return down the glass rather then across the surface.

 

[ChrisH]

Thanks for such a fast responce!

The CO2 from my reactors goes into the inlet tube for the filter train,

By this do you mean that you are putting the pipe inside the inlet tube to your filter?

Would it work if I made a coil out of tube and let the air bubbles run around the coil as it would always be incontact with water inside the pipe? I might have to have a play tonight!

Thanks!

Chris

 

[Lateral Line]

It would be better then simply letting the bubbles rush straight to the surface, yes. It is the basic idea behind the snail devices. You'd need to fiddle to get the angle right so that the bubbles moved, but flat enough to make sure they moved the slowest possible speed.

And yes, the CO2 delivery pipe goes directly into the pipe taking water from the tank to a big bucket Eheim with 2 extra canisters on it.

 

[ChrisH]

Do you think that this would work for diffusing the CO2 into the water?

basically the tube runs down the inside of the pipe, out through a hole in the bottom, and spirals up the outside, until it is pushed back in through a hole at the top. The end is then loose in the pipe.

Any opinions?

Many Thanks!

 

[ChrisH]

Mmm... I built a very basic test to see if this kind of DIY CO2 system would work for me, and bubbled the CO2 through a bucket of water overnight. I was quite alarmed to notice that the Ph dropped from 7.1 to below 5 (off my scale). Is this not really bad? Presumably the plants are not going to be using any CO2 at night so this seems like it has the potential for disaster?

The bubbles were being released about 3-5 seconds appart and bubbling to the surface so most of the gas should have been lost. Am I doing something very wrong??

Chris

 

[mark2513uk]

I'm new to this myself but have done some reasearch into diy co2 units and
the one that i have found looks interesting,maybe this will help

http/www.qsl.net/w2wdx/aquaria/diyco2.html

there is alot of reading but hopefully most of your questions will be answered

 

[Tocan]

Just built a DIY co2 setup with yeast and sugar. Should I keep it attached during the night concidering the plants wont use any during the night?