Couple of Pressurized Questions -

[MSU Fan]

I bought a 10 gallon CO2 tank back in the first week of September - the gauge is showing that it is mostly empty now.

1. How long should the 5, 10, and 20 gallon tanks last?

2. Do many of you find that your settings (of bpm) change over time? I am not sure what is going on with mine, but the settings were originally at 30-60ppm CO2, but lately, my CO2 went nuts for some reason - my fish were gasping and 2 died - did all the tests (Amm, Nitrite, Nitrate, Phosphates, GH, KH, PH). Everything was lined up :
Ammonia - 0
Nitrites - o
Nitrates - 10 (i need to increase - stupid wisteria used it all up)
Phosphates - 3-4
GH - 9 degrees
KH - 5 degrees
PH 6.0 (lowest on the PH card)

When I computed the CO2, behold, 5 KH and 6.0 PH = 150ppm CO2!!!

I turned the CO2 down (it was at 3-4 bpm, and now it is ~2bpm), and turned on all the airstones I had in the tanks (3). Now my PH is 7.0 and my CO2 level is ~15ppm.

Anyway, has anyone had this sort of thing happen to them? And for those of you who have pressurized setups, how often do you tweak the bpm to keep it lined up. Also, is there some way to buffer the water to keep the PH up more? I don't seem to have much in the way of a "comfort" zone where the PH/CO2 relationship is concerned. TIA

 

[rkilling1]

Either the setup you are using is leaking or your tank wasn't filled. It should last a lot longer then that. BTW, 2 BPM sounds pretty low. I have mine set at 3.5 BPS.

My settings have not changed since the last time I adjusted it. What outlet pressure are you set at?

 

[rkilling1]

Forgot to mention that I have heard of people running into the same problem with their CO2 when the tank is almost empty. It's called "end of tank dump". If you have your needle valve controlling the output, then you shouldn't be seeing this. If you have your needle valve wide open, then this could be your problem. ie controlling the output with the regulator vs the needle valve.

 

[Lonewolfblue]

Actually you are talking about pounds, not gallons, lol. It's a 5lb, 10lb, and 20lb tanks. For a 10G, I would think a 10lb tank should last quite a long time. A 10lb on my 75G tank will probably last almost a year, as the 5lb I had on it lasted 6 months. And with the tank being only 10G, the bubble rate should have to be near as high as on a 75G. So for a 10lb tank, I would say much longer than a year.

If you have some Windex, use a paper towel to protect the surroundings and spray all the connections. If you see any bubbles, you have a leak. And with the tank being nearly empty, now's the best time to fix the problem. Check all the connections, at the tank, the bubble counters, solenoid if you have one, and needle valve. Just anywhere it looks like something is screwed into another part. And in a 10G tank, I don't think you would need more than 1 bubble per second, as that's all I'm doing in my 10G and my 29G. My 75G is the same, but I have 2 CO2 outputs going into the 75G, each running about 1.5 bubbles per second.

What is the output pressure? Should be set to anywhere between 8lbs and 15lbs.

As far as tank dump, they say the needle valve should help prevent this, but I don't think it does. At my last refill (this last Monday when I upgraded to a 20lb tank), when my main guage was decreasing, my secondary guage was increasing, up to 50psi, where I had to turn it back down. So, watch your guages when your main guage starts decreasing, as an increase in the econdary guage means more CO2. I looked at my bubble counters, and I couldn't tell how fast they were, til I lowered my secondary guage back to where it should be. That's called Tank Dump. Should be watched closely.

 

[MSU Fan]

Actually you are talking about pounds, not gallons, lol. It's a 5lb, 10lb, and 20lb tanks.

Yep - I sure made that confusing, didn't I? I am glad I could amuse you LWB, especially after the wolf eel story! So, for clarification, my CO2 tank is a 10lb tankand is dispensing at ~2 bubbles per second.

If you have some Windex, use a paper towel to protect the surroundings and spray all the connections. If you see any bubbles, you have a leak.

I have a bottle of windex with my name on it just waiting for me!

And in a 10G tank, I don't think you would need more than 1 bubble per second, as that's all I'm doing in my 10G and my 29G. My 75G is the same, but I have 2 CO2 outputs going into the 75G, each running about 1.5 bubbles per second.

Haha - 3rd confusing statement - my tank is a 75 gallon! Man, what was I drinking when I wrote this??

What is the output pressure? Should be set to anywhere between 8lbs and 15lbs.

As far as tank dump...At my last refill, when my main guage was decreasing, my secondary guage was increasing, up to 50psi, where I had to turn it back down.

This is pretty much what happened to me. I hadn't looked at the CO2 levels since I put the mister in the tank, and that was a couple of weeks ago. All of a sudden my fishies are having issues. I don't know what the 2nd gauge was at, but I am thinking ~40 (definitely higher than 20). Also, the BPS was more than 2 for sure - maybe 4-5. I will post the current settings later tonight and my other tank parameters - maybe a pic of the CO2 tank regulator.

 

[MSU Fan]

A little late on the response, but...my co2 tank is now empty, so I didn't take any pics. Both gauges read "0" (input and output) and there are no bubbles in the bubble counter.

Correction from above - it is a 5lb co2 tank, btw!

I need to get a refill and reset the system (my algae is loving this, btw).

 

[malkore]

I can get up to 6 months on a 5lb cylinder running my 75gallon setup. it runs 24/7...no airstones, no timers, no pH controllers, and I keep it just under 40ppm of CO2.

so, yours sounds a little leaky to me.

 

[Lonewolfblue]

Yup, same here, the 5lb I had before I upgraded to the 10lb bottle lasted approx. 6 months. The 10lb I have on there now has no leaks, so I'm guessing I should get about a year on it.

 

[Zezmo]

4-6 months on a 5lb on my 72 gallon tank. I use mist CO2 and run 4-6 BPS (at least).

Do you have a needle valve? A good needle valve will keep your BPS constant, and prevent end of tank dumps.

Many recomended getting them from Rex Grigg (clippard). I have not bought from him. But have only read good reports.

I have bought needle valves from these guys:
http://www.stcvalve.com/DIMENSION-FV.htm Which sell for $7.37 for an in-line needle valve.

http://www.stcvalve.com/DIMENSION-CV.htm which is $6.17 for a needle vavle with an NPT fitting. This will screw directly into a solenoid.

The second link has a chart, showing the flow rate versus number of turns. Look at the smooth/flat flow curve on the 1/8 npt valve. I have one of these on my main tank and it really gives me some fine control.

 

[MSU Fan]

Thanks for the help - my tank lasted ~3 1/2 months, so there probably was a leak. I also remember when I first set it up, some leaked out then too. Oh well. I refilled the tank, and I put pipe thread tape on the valve before installing my milwaukee ma957 regulator (it's not rex grigg, but good enough for now) on it.

I tested for leaks using the windex (thanks lwb), but was unable to identify any.

One thing I have noticed since installation (last thursday - 12/14) is that my output pressure keeps dropping to 0. is that normal? Right now I am running ~2 bps, but I haven't tested the water since I added the co2 again.

I will have to get back to you later this week with my results...