CO2 Regulator / Solenoid / Needle Valve

nice article zoom.. defn helps some diy loving folk!

dont forget weekly 50% water changes if u are going EI

well reason why i started on this was because i didnt have much experience with plants initially..i had learnt about photosynthesis in high school and was amazed that by a simple process of adding sugar water and yeast i could create co2 and inject that into the tank to incr growth.. also being a student, i would never have been able to afford a complete system/excel. i would still recommend this to a beginner esp if they have a low lit tank.. its a great lesson to see how it can improve growth.. when i had it in a low lit tank i almost had no issues (i did do regular yeast and sugar solution changes i must admit).. it was when i incr my lights did i start having problems..that was the next lesson i learnt..

i have a few questions for you though..

im just curious to know, what is considered "good quality"? because i must admit, my first co2 regulator i bought was the cheapest one i could lay my hands on.. im still using it for 3 years now..maybe i was lucky in the sense that it never leaked etc.. besides the needle being harder to calibrate specific bps, there were no issues.. it was pretty stable with the bps once set as well?

what would be the difference between a hospital grade and a entry co2 kit? because in my mind, injecting co2 would be injecting co2.. is it the quality? as in it wont break down easily? or easier to calibrate?

 

@shihr

Good quality imo would be something that is robust and will last. Something that is accurate... and something that will not leak. Pick them up and you will feel a weight difference. I think a good quality would be slightly more pricey (if you are comparing in the same supplier). The guys doing CO2 welding can always recommend what they are happy with. Remember they also use these as portable packs, and we all know what that means... usually banging around in the back of some unsecured bakkie. Chat to the manufacturers and you will get a general feeling for what is good quality and not.
Comes down to that same old fashioned term:
"RESEARCH"

The difference I can say with "hospital grade" and the other one I had was quality and more than likely performance. The entry level one leaked on me... possibly a dud buy? The hospitals need to make sure that the equipment they use will not fail on them... let's be honest here... if it fails, they start loosing court cases. The hospital grade stuff was also 100% brass, sealed unit, meaning there was not parts to come apart or fiddle. Obviously if the unit fails, you would replace it... but again... quality might not need replacing any time soon.
Chatting to my refrigeration mechanic at the office, he also says that needle valves need to be set, and he needs to know that what he sets it at is what it will stay at. If something changes, something breaks. So to him quality is something that keeps it's setting, and doesn't change. I've heard of stories of people using cheap needle valves, and having to recalibrate their bps every few days to ensure it's accuracy.

Oh, on a side note.... a regulator works off of pressure from the bottle. If I recall my bottle is at 5.1bar. Some regulators work fantastic under "high" pressure (5.1 is not really high in bottled air pressure terms), but as soon as the bottle starts emptying out, the pressure lessons. Some regulators have what is termed "low pressure dump". Meaning that when the pressure falls below a certain level, the regulator fails. Meaning EVERYTHING that is left in the bottle is released. In certain industries this isn't considered too bad.. HOWEVER.... you can imagine if suddenly a 0.5bar pressure of CO2 is suddenly released through your solenoid and needle valve and ultimately into your tank... It might not be a lot of pressure, or a huge amount of CO2... BUT... the pressure could be enough to irrepairably damage your solenoid and/or you needle valve... and ultimately dump enough CO2 into your tank over an extremely short period of time to cause big problems in the tank. (I.E killing your fish)

I would like to believe that the LPS "grade" regulators will not do this. My solenoid and needle valve is SA stuff, my regulator is still the original regulator that I bought. (ReefOctypus)

 

@slagter - your comments?
@wearsbunnyslippers - your comments?
@Rudi - your comments?

@Altum?

This thread is very one sided (i.e mine) and you guys with the set ups are all keeping very hush in the background

 

ok fair enough..

 

In my opinion a Co2 setup is safe. I had one running for about a year, and standing for more than a year doing nothing. No issues what so ever.

I understand most peoples objections to Co2. I used to have the same objections about it. I thought it was too expensive, too difficult to maintain, a pain in the ass when it was empty, etc. But after seeing the results in my own tank, I will always recommend it. I have also found a way of making it affordable. Ebay. I just paid R522 for a Dual Gauge reg, with solenoid and a needle valve, including shipping. I bought a 2kg bottle for R240 from builders. That's R762. For a complete Co2 kit. It's affordable. Easily. And the amount of money we spend on our tanks every month on unnecessary rubbish, is far more than R700 odd bucks. Just be picky and selective when buying things.

Obviously a big thing is diffusing the Co2. Getting the right diffuser for your tank is important. Making sure that you are using it optimally is critical. Silicone tubing is rubbish, in my opinion. I used to use it on my old system and it was always inefficient. I always had to check and recheck the needle valve. So the correct Co2 tubing is vital in making sure that none of your Co2 is going to waste.

Personally, I think that a heavily planted tank is amazing. To recreate a picture out of a river, in your own house, is one of the most stunning things you will ever do. I still prefer a nice planted tank to a reef aquarium. Seriously. I think that this hobby is changing locally. There is a big international movement that has already happened, and it's slowly going to happen here too. It's not that expensive, but the results scream out for themselves...

I will be back very soon...

 

On another note about safety...

Just remember that these things go through massive testing before being put on the market. They should not fail, at all. If the bottle explodes, the supplier and manufacturer could be held liable for damages. They don't want or need that trouble, therefore their products get tested to the max. Obviously, user error (IE: Being stupid) would not be a reason for them to worry. You need to secure the equipment properly, and nothing should ever go wrong.

 

@Zoom let me comment:
The end of tank dump is something that can happen with any single stage regulator. What happens is that the regulator "sees" a lower pressure in the bottle and opens up to compensate, and unfortunately allowing a large amount of CO2 to flow through and gas your fish and they die. Which is why you can't trust a regulator and just leave it for a few days. You must check it all the time. I think the best plan here is to buy a small kitchen scale and place your full CO2 bottle on this scale. Then recalibrate the scle to show 0 kg. Now you know when your bottle is near empty.

However, cheap needle valves can drift, and that is why people have to adjust them all the time to achieve a steady bubble count. This is especially true when the output gauge is set high to provide enough pressure for inline CO2 diffusors.

The way to overcome these obstacles is to buy a dual stage regulator. The second chamber acts as a buffer: it gets high pressure from the first chamber (after the first chamber decided to open up to compensate for lower pressure in the CO2 bottle), and then reacts by "closing off" a bit. No more end of tank dump issues.

The other thing is to buy a quality needle valve. A set and forget unit. Good ones are made by Clippard and Fabco, but the only true set and forget unit is made by Ideal Valve, about $100 plus shipping. It's been reported that a single stage regulator with an Ideal Valve needle valve is as good as a dual stage regulator with any other sort of needle valve.

So in the end it does not really come down to LFS vs Hospital/Lab grade equipment; rather, it is about choosing the correct items to work together to provide peace of mind.

 

I think the idea of buying medical grade equipment for a fish tank is absolutely crazy. Why would you want to spend thousands on something that could produce a "slightly" more stable bubble count? I think that the standard Co2 equipment you buy from the LFS is totally good enough to use and get constant good results.

Like I said in my previous post, the stuff is tested so rigorously, that the odds of malfunctions are very slim. A washer here or there is not a malfunction, it's wear and tear. Using the wrong tubing will cause unstable results. Using the wrong diffuser for your tank size will cause varying results. The check valves malfunctioning will cause issues. Bubble counters not installed properly will cause issues...

There are so many variables in this hobby, saying that you bought a cheaper reg/solenoid/needle valve, that works just fine, is not an excuse for inaccurate results unless all the other variables have been eliminated from the issues.

Seriously guys, it's not that difficult to set up and install a working pressurized Co2 system. It just takes patience to fine tune it.

 

@slagter I have to disagree with you. It is not about the stable bubble count. It is about the peace of mind knowing that it is unlikely to fail. Same reason why you shouldn't go driving on a long road trip with cheap retreads instead of quality tyres. Yes, you can buy a cheap regulator. You can also buy a cheap needle valve, solenoid, etc. Fit it nicely and check for leaks and you have a decent system. May work for years, even. Until the day you gas your fish...

 

I've already gassed all my fish. But it wasn't the fault of any of the Co2 equipment. It was my timer that failed. Didn't turn off the solenoid. Gassed all my fish. 2 breeding pairs of Bolivian Rams, 8 x Apistogramma trifasciata, 12 x corydoras, 4 x keyhole cichlids, 15 x rummynose tetras... I know all about gassing fish. Trust me. But my reg/solenoid/needle valve was not the cause...

I think your connection to cheap tyres is a bit of comparing apples to figs. Tyres on a car is totally different to a reliable Co2 system for a fish tank. If you can get an affordable Co2 system, that is known to work, on thousands of other peoples tanks, then why would you pay 5 times as much for the other kind? It's kind of like buying a Corsa, or buying a Rolls Royce. I wouldn't say it's retreads vs brand new tyres... Brand new tyres fail as well...

 

Zoom,really good write up.Just shows what can be had with a bit of research.
On the yeast based,home made Co2...with some work,attention to detail,this can be the results.


And this,same guy.


For myself,I did a yeast based Co2 for about 6 months with good results and minimal algae problems,even less when I started to regularly change the yeast bottles and running 3 bottles in line and keeping them at a stable temperature.I only switched to pressurised because I upgraded to a bigger tank.
On quality,sure it's important,I don't want to replace parts every 6 months and luckily my e-bay regulator is still running after a year and a half.But I have never seen a winning scape mention the type of regulator being used,single stage or dual stage,it won't make the plants grow better or improve your own skills.It just means you can't blame the equipment when you fail to grow your plants.

 

Totally! I agree 100%. Nice post.

 

Yes the tyres can fail, so can everything, the point is to minimise the risk. Here is a long description, taken from someone else, I can provide the link if you require it (edited slightly by me):

As you use the CO2 in your cylinder, it gets lighter and lighter. When you have used about 80-90% of the gas, the pressure starts to drop from the 800psi or so it had when it was just filled. If you keep drawing gas, it will drop to zero eventually. But you don't want to do that, because at about 500psi or so, the regulator becomes unstable.
When the critical pressure is reached, the regulator will dump the entire remaining contents of the tank into whatever comes after the regulator. When this happens, the pressure on the output side of the regulator will rise dramatically. You can try to protect your aquarium by putting a pressure relief valve set at 20 psi or so on the output side of the regulator so this excess gas will just be vented into the room that contains the cylinder.

Replace the tank when the pressure starts to drop, just like the gauge says. There is another reason to replace the CO2 cylinder when the pressure starts to drop. Catastrophic regulator failure described above frequently damages the regulator itself, often by making a hole in the diaphragm. This damage is not covered under warranty, it is your responsibility to ensure the CO2 cylinder is replaced before regulator failure occurs.

You can tell the tank is running out in a couple of ways. First, keep an eye on the high pressure gauge. When it begins to move off the 800psi or so it had originally, it is time to replace it. Another tool is to weigh the tank. The tare (empty) weight is usually stamped into the tank near the shoulder (ask your CO2 supplier to show you). Add a few kg's for the gauge and the rest is CO2. When 80% of the CO2 is gone, it is time to be careful.

Of course the best thing is just to replace the tank. But if you can't do that for a few days, one strategy is to shut off the master valve. One filling of the high pressure side of the regulator will last for several hours (see the section on leak testing). That way, if the tank starts to seriously empty the regulator will not dump the whole thing.

In an un-managed configuration, a CO2 tank after a year to ten years of faithful service will run out of gas. When this happens, the regulator which has been providing a steady outlet pressure of say 10 or 20 or 30 psi (depending on how you have it set up) will suddenly fail and dump the 2-400 psi gas straight into the appliance (reactor or whatever) that you are feeding.

There are three basic ways to manage your CO2 system and avoid end-of-tank failure. These are anticipation of end-of-tank, relieving the pressure pulse, or avoidance of the pressure pulse. Anticipation means that you track your CO2 usage or pressure and take steps to avoid the end-of-tank condition entirely. Relief of the pressure involves a special device designed to relieve the excess pressure during the pulse so that the rise at the appliance is small. Avoidance refers to using a regulator and associated control parts so that the pulse does not occur until the tank is totally exhausted, at which time the flow will stop.

Anticipation:

Anticipation is the simplest and cheapest solution. One way to anticipate end-of-tank is to weigh the tank regularly. You can expect it to deliver about the announced volume (in kg's of CO2). If you plot weight versus tank age in days it should be easy to guess about when you will have reduced its weight by the 2kgs or 5kgs of CO2 you bought. If you decide to replace it based on low weight, it would be interesting to empty it completely by opening the shutoff valve with the regulator removed to see (and weigh) how much gas actually remained.

Another way to anticipate end-of-tank is to closely monitor the high-pressure gauge on your regulator (if it has one). The pressure will START to drop weeks before an end-of-tank dump occurs.

Once an end-of-tank condition is anticipated, you can simply turn the gas off at night and when you are away until you have a chance to refill your tank.

Sadly, anticipation is unforgiving of inattention and if you don't notice the end-of-tank a disaster can occur. If your failure occurs during the day when your plants are metabolically active and producing lots of oxygen then no problem may ensue. Or if your tank is open-top, so that there is lots of atmospheric oxygen in contact with the water surface you are reasonably safe. But if your top has a tight fitting cover and the dump occurs when lights are out and your tank is heavily populated with fish, the CO2 in the gap between the water surface and the cover may physically drive off all oxygen, at which point your fish can suffocate.

Relief:

Relief is based on the idea that the excess gas that would be delivered during an end-of-tank dump is simply vented into the atmosphere somewhere. The most convenient place to vent is usually right near your tank, but you can also plumb a plastic vent line to a more convenient location if desired. A relief system should also be tested on a routine basis to make sure that it is continuing to provide the protection it was designed to give.

Pressure relief devices come in two kinds: manufactured valves and water-head homebrew devices. Many valve companies make pressure relief valves that will trigger at about 20 psi which should suit most users. If you have a higher operating pressure, make sure you select a valve that vents at a pressure just a little higher than your norm.

You can also make a pressure relief device at home if you tap your system at a point where the pressure is supposed to be low (like right before the appliance, after any pressure-reducing check valve). At this point the pressure should be only a few feet of water (2 feet of water is about 1psi). Simply take a 6 foot piece of 3" plastic sewer pipe, put a plastic cap on one end, set it upright open end up and fill with water to about a foot from the top. Run a long piece of plastic tube or airhose down to the bottom of the sewer pipe and connect the other end to your CO2 line. As long as the pressure is less than the five feet of water in the sewer pipe, the pipe will do nothing. When the pressure rises to more than five feet of water, the excess gas will vent out thru the airhose, down to the bottom of the sewer pipe, and bubbling out the top. You can enhance this design by also capping the top and running a CO2 vent line made of plastic water pipe out to a more convenient location if you wish. Ensure the low end of the hose from the CO2 system stays at the bottom of the sewer pipe by weighing it down. Or use a rigid plastic pipe to convey the CO2 down to the bottom of the sewer pipe.

Avoidance:

A third strategy for managing end-of-tank failure is avoidance, referring to selecting system components so that failure simply does not occur. This can be an expensive strategy but should be considered if the stakes are high (such as many tanks or a very expensive setup). Avoidance strategies are like relief strategies in that they involving using different hardware.

One place to attack avoidance is at the regulator. There are two stage regulators (where one regulator feeds another, do not confuse with two gauge regulators), down-stream regulators (that regulate based on output pressure, not input pressure), and better grade regulators (that undergo much less pressure rise as the input pressure falls). All these strategies increase the cost of the system. Whether they are worth it depends on many too many factors for one person to attempt to decide for another. Generally speaking, if you are handy with tools and savvy enough to do your own CO2 system design, you should expect avoidance to add an extra R1000-R3000 to the cost of your CO2 system.

Take this information and use it. I want to point out that I am NOT against CO2 injection. I just want to stress the fact that care needs to be taken and personally I prefer the avoidance method. If you have equipment that you trust, then all is well.

 

@Rudi...yes I have seen some great results with DIY CO2 and you are right, it works well for small tanks if you change out regularly and keep the temperature of the mix constant. On bigger tanks Excel is actually better and cheaper. Pressurised CO2 is, however, the best thing on bigger tanks. If not, then set the goal for a non-CO2 tank and plant accordingly, not to mention the lower light.

 

This is how I do it.

 

The information I wrote above mentioned that the pressure will START to drop "weeks" before end-of-tank dump occurs. I have seen it happen within a day or two. That was because my output pressure was set at 25psi to provide enough level for an inline diffuser. Anybody else with a similar experience?

 

By now I approximately know how long my Co2 cylinder last and start to keep an eye on it a week or two before the "expiry date" is due.When I notice the pressure falling I also keep an eye on the working pressure,the second gauge.When it starts to rise and the bubble rate increases,I know it's time to shut it down and change the cylinder.

 

@slagter... you missed the ENTIRE point of the thread here.

The point I was making is that medical grade equipment is CHEAPER than LPS grade. Meaning you get BETTER quality for less price. Personally I think companies like Milwaukee and SAGA are ripping the prices because CO2 is seen as a "elite club" that only the rich can afford.

I'm trying to break this mentality a bit on TASA. A few weeks ago I read a very interesting article that plants can ADAPT to light conditions... meaning they have the ability to use less than optimum light, however in order to do this, you need to ensure that the CO2 supply is suitable. The article went along the lines:
Plants have energy reserves.
These energy reserves are used in (1) CO2 function and (2) light function.
IF the CO2 is suitable, the plant can ADAPT to less than optimum lighting.
IF the light is suitable, the plant CANNOT adapt to less than optimum CO2.

So, Bottom line, get some CO2 going, and THEN focus on lighting.
I'm just trying to prove that it's not as expensive as the LPS sell it at.

 

:congrats: i totally agree..

 

@Laure - Nice write up. I wouldn't mind that link, if it's not too much trouble. You just need to watch your gear. Make sure it's functioning correctly. It will be a pain the first time you need to check how long your Co2 bottle lasts, but after the first time you will always have a good estimate on the time it will take to empty. Then make sure you fill it before that time period runs out.

@Zoom - I think I did miss the point then. The problem with the way you describe setting up a Co2 system, even though it is easy enough to do, is that it's a mission. People would rather buy a complete unit, than have to buy the separate parts and put it together themselves. It may be inexperience on the side of the hobbiest, or it may be pure and utter laziness, but what ever it comes down to, if something does fail, then the person only has them self to blame. That's the problem with this hobby. If something goes wrong, people look for other people to blame. I've seen it a million times.

But, ok, now that I have rethunk your original post, yes. It is a super easy thing to set up. It's amazing how, when you actually put a little thought into what you are doing, you can get amazing results for a fraction of the cost. Personally, if you could package that idea of yours, I think you would catch the market. I really think this hobby is about to change on the freshwater side. The aim of planted tanks is really coming into focus here. It's people like Wearsbunnyslippers, Algae Wizard, Laure, Zoom and the rest of the bunch from APSA, that have made the planted side of the hobby what it is in this country. Sure, we all try to have a really nice tank at the end of the day, but there aren't many of us that can look at our tanks and say "Wow". But what do these systems have in common? Co2. Lighting. Ferts. Regular maintenance. All it takes is a little effort.

Also, with regards to that post about plants adapting, the biggest part of that scenario is ferts. This Co2 no Co2 battle will rage for a while still, until the majority of people see the results across many tanks locally. But Ferts is an even bigger debate in my mind. And until we get proper planted tank substrates, like ADA or Controsoil, we will battle to see the results that most of the world gets.

So in my opinion, yes, Co2 is king. Spend your money wisely on Co2 systems, and you needn't have to fork out huge money on one. Then look at good ferts, then look at lighting.