How to set up a CO2 system

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mudraker

Aquarium Advice Addict
Joined
May 28, 2009
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Alaska
I’ve seen several posts lately asking questions on regulated CO2 systems. A lot of people (myself included) seem a little overwhelmed or intimidated by the set up process. I am posting photos the hook up I did last night. Mine is a Milwaukee MA957, with a built in solenoid and bubble counter, but the general consensus is that the assembly is basically the same. More than anything, I hope to show the timid among us that it is actually a very simple process. I also disliked the instructions on the box. They are printed on the opposite side of the parts diagram. You have to keep turning the box around to figure out what they are referring to.

This is my first time doing this.

It was 100% easier to put together and start than any of the numerous DIY systems I’ve made.

My CO2 cylander is a 20 gallon size (long story) and so I have to lay it on its side to hide it under the tank, so the bubble counter was taken off and rethreaded into the solenoid to stand upright, so it may look a little different than other setups, but the assembly process will be exactly the same.

The only tool needed was a large adjustable wrench. Also, make sure you have a check valve if one wasn’t included (mine didn’t) in your setup. Stainless or brass is best. Plastic will work for awhile, but CO2 will degrade it after awhile. You will also save yourself a lot of work and expense later if you start with CO2 grade tubing. Run-of-the-mill airline tubing will work, but will also degrade over the months and will need to be replaced often.

So here goes!

Hold the regulator upside down and seat the O ring into the neck where the regulator will screw onto the canister. This is what will seal the regulator. One side of the O ring is bigger around than the other. The smaller side goes face down into the regulator and the larger side will face into the cylinder.

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With your fingers, gently twist the brass nut onto the stem of the cylinder. When you hear a light pop you will know you have achieved a seal.

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Use the wrench to tighten down further. I wrapped the nut with a paper towel to prevent scratching up the brass, which is very soft and easy to scratch with tools. Turn until it is snug. You don’t want to wrench it down too hard.

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Tada!

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(I haven't figured out how to be able to attach more than four photos at a time on a thread, so I am just going to post the rest of this in a reply right after this. Hopefully, no one will post a reply before I finish up and the photos will be in the correct order I placed them.)
 
Next, make sure the needle valve (the round brass knob on the end) is turned all the way to the right. Unscrew the brass ring (the top) of the bubble counter. It came off very easily by hand. Fill it about half way with clean water. Screw the top back on. Make sure it is snug.

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Set the regulator adjustment knob, which comes unattached, into the spot under the pressure gauges. Screw it in counter clockwise very, very gently until there is no tension felt. It will be real loose feeling. This kind of scared me but it worked. The instructions say if the knob is tight, the pressure from the canister will break the gauges when you turn the system on.

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Turn that puppy on! Do this by turning the knob on the cylinder slowly to the left. You will hear a slight pop and the gauge on the left will show pressure. Open it all the way.

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The instructions say to plug in the solenoid. It is designed to be plugged into a timer or ph controller. (If you don't have either one, you can still plug it into a regular outlet until you can upgrade.) Open the needle valve (the knob on the end of the bubble counter) all the way by turning counter clockwise (left.) Now turn the adjustment knob (the black one left loose earlier) clockwise (right) until the low pressure gauge (the one on the right) shows 10 pounds or less of pressure. Voila, a mass of bubbles in the bubble counter.

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Almost there, will post yet another reply to my own post to continue.
 
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Unplug the solenoid and prepare to attach your tubing. Unscrew the compression fitting (brass nut type thing) on top of the bubble counter.

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Slide your tubing through the fitting and attach it to the nipple. Slide the nut down the tubing and screw it down until it is finger tight. I just used the tubing, check valve etc. I already had set up in the tank for my DIY system. If you are starting from scratch, be sure to install your check valve in the tubing before letting it rip. Same goes for bubble counter and any other goodies you have to attach to the tubing, both inside and out of the aquarium. As advised in a different post, I am using a glass/ceramic diffuser I already had and placed it closely and directly under the intake of my external filter.

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Once you have your goodies and whatever diffusion method ready to go, plug your solenoid back in. If you are using a glass diffuser (yes, I know I should be using and inline diffuser, but that will have to wait) it might be wise to keep it just under the waterline until you are sure you won’t be needing to make any adjustments, like it starts making racket, etc.

I had to turn down the adjustment knob immediately because it was fizzing out in the bubble counter too high. It took about a half hour for it to flow consistently and I could adjust it to one bubble per second. I used that time to throw away my DIY pop bottles.

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(No conniption fits please, plastic recycling is still unavailable where I live.)

I had to crank it up a little when I got up this morning, but it remained stable all day while I was at work. Yes, I’m starting low on the bubble count.

Please point out any flaws in this post.

I’m hoping to help take the mystery out of putting a system together and show that it really is as easy as they say.

Since putting this together last night, I now know it is easier to assemble than a new canister filter - hands down.
 
The only suggestion I would make is to replace the plastic o-ring with a permaseal. These make it much easier to get a good seal and don't have to be replaced every time that you get your cylinder refilled. Just make sure that if the place you take your cylinder to swaps out the cylinders, that you either remove the permaseal before taking it in or that you make sure to ask them to move it to the new cylinder.
 
That's a very good point.

I will add that to my never ending and always growing list of hardware needs.
 
Thanks Fort.

Mom2, I was like you, trying to figure out what system to go with, not sure what direction to take. It was intimidating but its really worth it. I especially didn't like the way they use technical jargon to describe a nob or a nut. Makes it seem much harder than it is.
 
I know exactly what you mean. It's a huge step in expense and commitment.

I always swore I'd stick to low light plants: easy to grow, less expence on substrate, fertz, co2, light systems, etc.

With patience and persistance you can keep a truly beautiful aquarium.

Then I met a really arrogant high light enthusiast who gave me a lot of clippings. The guy was totally pompous and put down my lowlight tanks without ever having seen them. He was a total jerk but I had to admit his 50L was stunning. And the plants were free.

That was last Feb. and I stuggled with DIY CO2 with mixed results since then. So when the mister asked what I wanted for Christmas...
 
I was curious about purchasing this set up online. I would be getting a smaller tank due to prices and room availability. But overall this thread is really helpful and the parts were easy to find online and fairly priced. I'm still new to the whole pressured CO2. Would you know what the bubble count should be for my 29G, medium planted. And I was hoping you would know how long your 20g tank would last, so I could use that as a base for a smaller tank. I was thinking a 10lb Aluminum cylinder.
 
Welcome to AA!

the bubble count is not necessarily important, depending on how you control the selenoid. 1 bbs should be a good steady flow rate. On my 29, a 5lb tank lasted about 3 months. I was using a pH controller though, so that probably conserves some CO2 versus using timers.
 
Fort would definately know better than I because this is my first time with using regulated co2.

FYI, I saw a posting on a different site that advised the Perma Seal is incompatible with this particular type of regulator and to stick with the factory o rings. It did come with two. I rubberbanded the second one to the until so I don't misplace it.

I'll do additional research before the time comes to refill.
 
FWIW, I have never even changed my orings, or used perma seal for that matter, and never have had a leak.
 
you will eventually get liquid co2 going into your tank with the co2 canister being on its side like that...
 
Maybe just prop up the head with a couple opposing 2x4 wedges to keep the liquid level from ever reaching the regulator. If it reaches the regulator, that's bad. When full the liquid level will be much, much higher. At the bare minimum you should have a 45 degree angle. Be careful.
 
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I was actually going to ask about the cylinder being on its side. Everything I've read/heard says that is not good for the valve and regulator. Have you had any issues?
 
I was actually going to ask about the cylinder being on its side. Everything I've read/heard says that is not good for the valve and regulator. Have you had any issues?

Not at all. I did prop it up as you suggested.

I appreciated the info though. I just didn't have time respond at the time. So I'll say thanks now!

Thankfully, I got a new stand for the tank, and as soon I have time, will replace it with the old one. I will be able keep the cylander upright then.


About how much was the whole setup?

The regulator was a gift, but I see the Milwaukee MA95 online costing $80-$90. You can probably get it for much less without the electric selinoid. When I switch tanks out I am going to take the selinoid off, as I decided I really don't want or need to put it on a timer or ph controller.

The CO2 was outrageous, but costs are very, very high were I live in Alaska. So, that price is going to vary greatly depending on where you live and if you buy your own cylander and have it fillled, or some places you pay a base price for a full one and then trade it for another for a cheaper price when its empty.

I already had CO2 tubing, which lasts longer than regular air tubing. I forgot the price, so it wasn't too much more than regular airline tubing.

I already had a glass diffuser at the time and it wasn't much, less than $5.

I bought two imported stainless steel check valves for $16, shipping included.

I later bought an inline diffuser for about $20.

For me, the expense of it all was worth every cent, and I'm a tightwad!
 
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