Pressurized CO2 - lets do it

[tsonnenl]

Background: 72g planted tank, 2 x 96W AHSupply kit in custom canopy. (2.7 wpg)

I'm deep into my pressurized CO2 research, but there are a few things that I am unclear on.

How necessary would a pH controller be with the Milwaukee needle valve, solenoid valve, and bubble counter combo? $160 with, $76 without is a big difference. My tap water is almost neutral and I luckily have never had any problems with pH whatsoever. Will the pH be that drastically affected to warrant another 80 bucks?

Am I right, that CO2 at night raises the pH? Is there a way to have it automatically turn off at night to lessen the effect on pH? There's nothing to plug into my timer, right?

What size tank should I go for? I'm interested in both the volume and in the length, width, and height. Obviously it would have to fit in my stand.

Is the Milwaukee unit generally accepted as the best option, much like AHSupply is to lighting? I haven't found too many alternatives mentioned.

Thanks in advance. I hate spending money on things I don't understand completely.

 

[astroguy]

No, CO2 diminishes the pH (2H2O+CO2 <-> HCO3- + H3O+ -> more acidic). It is generally worse at night since the plants do not "breathe" and thus do not consume the CO2. That is generally true even if there is no CO2 insuflated.

As for the rest, I cannot help.

 

[astroguy]

I must state it more correctly: at night there is no photosynthesis, so no CO2 is used. But the plants "breathe" (O2), so some argue that one could insufflate O2 (oxygen) during the night, so that the fishes also get some O2.

 

[Mr Burns]

how much will the addition of CO2 change the pH? in my neighborhood, we have very high pH...it's like, stupid high. i use Aquarium Pharmaceuticals Proper pH 7.0 to control it when doing water changes, but it's my understanding that i can't use a buffering agent with plants/co2....

 

[Guest]

http://www.drsfostersmith.com/produ...tchallany&Ntx=mode+matchallany&Np=1&N=0&Nty=1

"This economical semi-automatic CO2 injection system is ideal for keeping plants lush and green in planted freshwater aquariums up to 200 gallons. Assembly is easy, and in no time your system will inject CO2 into your aquarium and automatically shut off at night when your plants start to take in oxygen. You need only monitor CO2 levels and add buffers when necessary. CO2 bottle not included. "

My wife bought me this for a gift (Hey she tried really hard, gotta give her credit, even if it's prolly not the purchase I'd have made) Not the cheapest thing out there by any means, but it does come with a timer, so you can time it to go on and off with your lights. I haven't actually set it up yet (it's for something still being planned), but this way it would be off at night, saving co2 and keeping the ph from droping too much when the lights are out.

 

[Guest]

The Milwaukee unit can be used with a timer as well.

You don't need a pH controller. In fact most hobbyist do without one. You could hook the solenoid to a timer if you wished. You say your tap water is neutral but what we really need to know is the kH. Well that's not right. You need to take a resting pH of your tap water after it has sat for 12 hours and 24 hours.

As for what size tank you said it yourself. It needs to fit in your stand.

Mr. Burns How far do you want to drop it? You could drop it quite a ways but your fish might not like the high CO2 levels. If you take a look at the pH/kH/CO2 chart you can see what your starting pH and kH are and see how far you can safely drop it. I have a very large .pdf version of the chart posted at my FAQ.

 

[tsonnenl]

Thanks for the quick responses.

CC-What would you have bought if that unit wasn't it?

Can you guys give me a target for bottle size? What size would be ideal for a 72g tank and how long would it last? I have nothing to compare things to.

I imagine that I would plumb it into the intake of my eheim 2026. Would the tubing hold up to the carbonic acid? I can't quite gague the severity of its effects. Annoyance or catastrophe...

 

[astroguy]

Variation of pH? This all depends on your water's buffer capacity. if your water is soft, it may vary significantly, while if your water is hard, there are sufficient minerals to act as a buffer. You can use a test to see what your GH is. You can use a buffer with plants. However, I suggest not to use too many artificial chemicals, in this case the proper pH buffer. Look first at your water hardness. Is it soft? is it hard? If it is really soft, look at the variation over a week and see if this is acceptable. If not, then use the buffer. However, do not use too frequently. Depending on the type of fishes you have they may not appreciate and die. For example tetras prefer acidic and soft water.

 

[astroguy]

I think there are special tubing and valves for CO2 on the market. Make sure you have them. Make sure that you have a one-way valve to make sure that no syphoning happens.

 

[Mr Burns]

rex - our tap water is pretty hard and pH is roughly 8 and i prefer to have neutral water. i only have a simple color chart test right now, but when you put the drops in and it comes out royal blue, you know that's high. i'll do a resting pH test tomorrow and see what it comes up with. why is it important for the water to rest? also, since i'm only in the planning stage and don't have plants, i don't know the KH, but i can probably find that out next week. the numbers on the chart, is that the CO2 ppm or bpm; how is the chart to be read?

 

[betowess]

A 15 or 20 lb tank should last a year. A 10lb for at least 6 months I would think. Usually people measure CO2 in ppm.

 

[Mr Burns]

CC-What would you have bought if that unit wasn't it?

Can you guys give me a target for bottle size? What size would be ideal for a 72g tank and how long would it last? I have nothing to compare things to.

i'd like to know that too, CC...i'll have a 70gal tank also, and that kit looks pretty complete to me as long as i can put a y-connector at the end of the tubing so i can feed it into my two powerheads... i don't need a whole lot of CO2, and maybe a 15lb tank should last me a full year, but i don't want to break the bank on this fancy-shmancy stuff either.

 

[betowess]

A ten lb tank is around $70 to 80 buckos filled. Some suggest renting that way you don't have to have it pressure tested to be legal each year. But a way around that is to turn it in just before your year is up because refills are like $10 bucks for a 10lb tank. So the tank isn't that big a part of your expense. Though I suppose all the components do add up when you first buy 'em. HTH

 

[Guest]

It's in ppm. Until you know the kH I really can't tell you if you can get the pH down to 7.

 

[Guest]

The hydro-test is good for five years. So if someone tells you it needs to be tested each year they are ripping you off.

Also you are much better off to run the reactor on the OUTPUT side of the cannister filter to avoid reducing the flow coming into the pump. Most cannister filters use a push style pump and rely on a siphon to bring the water to the cannister.

 

[Guest]

even if it's prolly not the purchase I'd have made)

CC-What would you have bought if that unit wasn't it?

good question.

I hadn't gotten to the point of doing all my research, so I don't have a straight-up answer.

I would have probably searched for individual components.

See, my next co2 project is for my basement. I have 3 tanks down there, really tired of doing DIY co2 on each one. So eventually, I want to have 1 co2 tank, feeding 3 aquaria. I don't know how to do this yet, haven't done the research, and I'm out of money.

Now, would I get this setup for a single tank? Maybe, maybe not.

I realize there are cheaper ways to accomplish the same thing, but I like the convenience of a "package deal." I also know that a reactor, hooked up in-line w/ the cannister filter, is more efficient than a diffuser, such as this unit has. Having said that, I'm still using a diffuser on my 90 gallon aq. In terms of plant growth, pearling, and overall tank health, I get exactly what I wanted. The only drawback I see is that my co2 tank doesn't last as long, due to the inefficiency factor(s). I still get 6-7 months from a 5 lb. co2 tank.

 

[Mr Burns]

rex - i understand that. i probably won't even bother testing until i start construction.

CC - so it's the diffusor that's inefficient compared to a reactor? functionally speaking in terms of CO2 delivery, what are the differences between the two methods (meaning, how does a reactor work and is it worth DIYing)? i was planning on feeding a CO2 line into the water uptake tube of each UGF power head so that (hopefully) it dissolves into the water on it's way up to the power head, and then really dissolves when it gets into the impellor housing and rushed to the output. is that a dumb idea? how long does a typical DIY yeast supply last for you, and are there variations on the mixture that will help it last longer?

asking all these questions, i feel like the guy guarding the bridge in monty python... gotta learn somehow...

 

[Guest]

Monty, where to start...

First, I cannot stress this enough, even for a moderately planted tank, DON'T use a UGF. the roots of plants will grow into it, causing dead spots where crap builds up. there's another reason a ugf is bad for the plant roots, I cannot remember what it is right now. If you do the ugf, you will regret it in the long run. Get a cannister, or even a hob will be better than a ugf.

DIY co2, gotta change the mixture every 14-20 days, in my case. Also, during the course of each mixture, the co2 ouput is inconsistant, and cannot be controlled. output depends on many factors, how much yeast/sugar, what kind of yeast you use, even room temperature can make adifference. Mixing new batches gets old in a hurry.

http://www.thekrib.com/Plants/CO2/

I think many of your questions can be answered here. I studied the hell out of the krib before my first planted tank. There may be more up to date info out there, but I got a lot out of this place. Explanations there will be much better than what I can give you.

I use the diffuser only because I don't like doing diy plumbing stuff, and the diffuser was cheap.

 

[Mr Burns]

ok, so ixnay on the UGFay...got it. kind of a bummer, but understandable. thanks cc.

i've already listed the plants i'm going to start with, but if they do well i am going to expand, so that in combination with my lighting, i do/will need the CO2. with this kit http://www.aquatic-store.com/en-us/p_61.html , i would just need a 5lbs tank, a power head, and that's it? is there any way i can get the same line fed to opposite ends of the tank somehow, or is one source going to be enough in a tank that's 55" long? is it possible to have CO2 fed to the cannister filter output on one end, then on the opposite end have a power head being fed a CO2 line?

which would be better for the money - the aquatic store combo or the dr. foster and smith combo? i've got a heavy duty timer that my lights are going to be run off of, so i don't need the timer for the solenoid and i'm not sure how necessary a bubble counter is...

thanks for being patient with me in my endless planning... oy vey

 

[Guest]

That kit has a single gauge, never used that kind. The dual gauge type tells you tank pressure, and out put pressure. single gauge, i don't know.

One source is enough for the tank, depending on how you do it.

i would just need a 5lbs tank, a power head, and that's it?

A co2 reactor is not just a powerhead smashing up bubbles. A diffuser would be more efficient than that.


http://www.aquabotanic.com/abstore/en-us/dept_3.html This link has examples of in-tank reactors, and in-line reactors.

I kndly request you to please go to that link i posted for the krib and read some more co2 articles. I don't mean to be rude, but you need more background on the entirety of how pressurized systems work, end to end. Or google up some other articles, please.

Please try to keep in mind that I have set up ONE pressurized co2 system in my entire life!

My system

5 lb co2 tank
dual stage regulator
needle valve
bubble counter
diffuser
co2 proof tubing.

I went for simple and less efficient. I think you can see my reluctance to advise you on exactly how to set up your particular system, just due to my inexperience with the sort of things you are suggesting.