Question Regarding Co2 Tank

[Aquabum]

I'm completely new at this, so please bear with me. I have a 5lb Co2 cylinder on order, but I have a few questions.

1. How long does a 5lb tank last for a 29 gal.?

2. Which regulator is the best, Milwaukee, or JBJ?

3. When should I refill the tank (Psi)?

Thanks in advance.

Lissette

[reiverix]

1. I get 3 months out of a 5lb tank on my 75g. But, that's not to say you will get around 7 months on a 29g. It will depend on how much CO2 you need to inject to get the desired ppm. Someone help me here, but does a higher KH need more CO2 to bring down the pH :confused:

2. I use a JBJ but would have no problem using a Milwaukee either

3. When the pressure starts dropping I watch it very closely. That's when I plan for a refill come the next weekend. I've heard about sudden CO2 discharges into the aquarium so I don't take any chances.


Hope this helps. You won't regret going compressed. Oh and I'll also add that I recently changed out my DIY reactor for a ceramic diffuser and I had to actually lower my bubble count. Shows how sucky my DIY skills really are :D I'm hoping this will extend the life of my CO2 tank.

[Aquabum]

Thanks reiverix. I got sick of the DIY thingy, and now I'm looking forward to this change. No more mixing, measuring and spilling stuff. Adios.

But now you have me wondering about the co2 discharge (ok, getting nervous). I've never heard of it before. Can you tell me a bit more?

As for the regulator, it's a tough decision then. I guess they're both good. I'll decide by tomorrow. Now, to find a store where I can get a good deal for it.

Thanks again.

Lissette ;)

[itstheantitang]

I know nothing about co2 discharge, but I assume if you buy a high quality regulator it should never happen.

[phanmc]

A CO2 dishcarge occurs when the pressure in the CO2 tank drops below a certain limit, releasing the entire remaining CO2 in the tank. You definately want to refill your tank before that happens. Luckily, many regulators mark when its time to replace the CO2 tank on the psi indicator.

[Aquabum]

I see. So in other words, this discharge is controlled by the regulator. Watching the tank pressure drop slightly and getting it refilled quickly, is a 'better to be safe, than sorry' kind of thing.

I gotcha.

Thanks.

[phanmc]

For clarification, the regulator controls the CO2 discharge to a level set by you. The regulator is able to maintain control as long as the psi (pressure) remains above a certain limit. Once the psi dips below the limit, the regulator will not be able to function properly and the entire contents of the CO2 tank will be released in a massive discharge.

[ashdavid]

1. I get 3 months out of a 5lb tank on my 75g. But, that's not to say you will get around 7 months on a 29g. It will depend on how much CO2 you need to inject to get the desired ppm. Someone help me here, but does a higher KH need more CO2 to bring down the pH :confused:

2. I use a JBJ but would have no problem using a Milwaukee either

3. When the pressure starts dropping I watch it very closely. That's when I plan for a refill come the next weekend. I've heard about sudden CO2 discharges into the aquarium so I don't take any chances.


Hope this helps. You won't regret going compressed. Oh and I'll also add that I recently changed out my DIY reactor for a ceramic diffuser and I had to actually lower my bubble count. Shows how sucky my DIY skills really are :D I'm hoping this will extend the life of my CO2 tank.

No a high KH will not affect the amount of Co2 going into the water to get the same Co2 ppm. Eg, thinking simply, a Kh of 10 and ph of 8 will give you Co2 of 3ppm, now if you bring the ph down to 7 this will give you a Co2 level of 30 ppm and lowering the PH by 1 point. Thinking along the same lines with a KH of 1 and PH of 7, this will give a Co2 levl of 3ppm. Now if you lowered the PH to 6 this will give a Co2 level of 30ppm, the same Co2 level as before and the same as before a ph drop of 1 point. So the KH will not affect how much Co2 you have to add.

As for your question aquabum it is hard to tell how much you will get out of your 5lb tank, it will depend how effeciently your diffuser works ,how much surface movement you have and also how many plants and photosynthesis rates. Even on a heavily planted tank you should get at least 3-4 months or more out of that tank. At first make sure you monitor PH and KH levels to see how much Co2 you have in the tank, and most importantly watch your fish for signs of stress. Also it is expensive but a great way to do a planted tank and that is by using a PH controler, this will ensure that too much Co2 is not added.

[Aquabum]

Okay, now that's scary.

Say for example a tank holds a pressure of 600 to 1000 psi. At what level should I be refilling my tank when it drops?

I appreciate the input.

Lissette

[djlen]

With today's improved regulators, that 'discharge' is a rarity. I've forgotten on occasion and tanks have gone bone dry with no blowouts. That's not to say that is can't happen and it's good practice to change out tanks when the pressure starts to drop. At 600# there is very little gas left in the tank so you're not wasting much by changing them out at that point.
Longevity of a tank is pretty much based on bubble rate. For longer life, use a diffuser that will give you the ppm them most efficiently.

Len

[ashdavid]

You can get an adjustment valve that you can plumb in after the regulator that you can ajust to the smallest of incriments and this will prevent what Phanmc is taking about. As the pressue drops so dose the Co2 discharge rate due to there not being enough pressure to pass the valve.

[Aquabum]

Ashdavid, thanks for the info. I'll look into an efficient way to dissolve the co2 in the tank. I'll most likely use the DIY method.

I'll be monitoring everything from the moment I start injecting co2. I certainly don't want to lose my fish. I've had them for nearly a year now, and I'm very attached.

Lissette