CO2 Dump!
October 20th, 2008
After the catfish convention auction, I came home and started acclimating the new bristlenose plecos that I got. I putting them in a 20L quarantine tank, and when I turned around I noticed that none of the sunfish or killies that usually swarm the front of the tank were there. Eventually, I spotted a few of the sunnies dug into the Ranalisma rostrata, and a few others swimming awkwardly at the water surface.
Immediately, I knew what had happened; the CO2 tank ran out, and dumped a ton of CO2 into the aquarium all at once. Right away, I pulled out my Python hose, and did a 50% water change. I also borrowed an air pump from another tank, and threw an airstone into the 40G. At that point, all I could do is wait and hope that I wasn’t too late.
I’m happy to report that despite some really dire looking fish, nearly all of the fish survived as of today. I only have one sunfish confirmed dead, and all killies are accounted for. I was lucky.
So, now the question is what can I do to prevent this from happening again? Well, two things come to mind:
1. I could add a pH controller to control the solenoid on my CO2 tank. If the tank suddenly started dumping, the pH controller would shut off the flow of CO2 once the pH dropped below a certain level. Unfortunately, this is not the cheapest solution.
2. I could attach a low-pressure regulator to the regulator I currently have. This would detect the low pressure that causes a CO2 dump, and vent that gas to the room, instead of the aquarium. The downside to this is that I already have a 3-way manifold on my regulator, which is pretty heavy. I’m not confident that the low-pressure regulator could support that weight.
So, I’m not sure what I’m going to do. At this point, I should have at least 6 months to decide before this could happen again. It’s not even a guarantee that it will happen again. That said, I don’t want to take any chances. Does anyone else have any alternative suggestions for what I could do to prevent this from happening in the future?
October 20th, 2008 at 8:00 pm
I’ve never put CO2 onto my tanks, but I do controls on a larger scale for work. Why would running out of CO2 dump CO2 into your aquarium and how would a regulator help?
October 20th, 2008 at 10:00 pm
You could try 3 Ideal 52-1-12 Needle Valves
I believe I saw somewhere that they work well against end of tank dumps. They are not cheap though.
October 20th, 2008 at 10:12 pm
I had this happen to me once, luckily I had no fish in the aquarium at the time
October 21st, 2008 at 1:35 pm
m@, from thekrib, this is what causes the dump:
http://www.thekrib.com/Plants/CO2/dumping.html
October 21st, 2008 at 2:11 pm
I just came across another potential solution for my particular Milwaukee regulator:
http://www.plantedtank.net/forums/equipment/49769-i-fear-eotd-what-do-you.html
Basically, I need to set my low-pressure gauge higher than I have it to minimize the end-of-tank-dump problem. Currently, it’s set right around 20psi. I’m going to try increasing it to 30-35psi, and see how that goes. If that fails, I’ll investigate The Ideal 52-1-12 needle valves, but I’d rather not drop that much cash on those right now.
October 21st, 2008 at 2:26 pm
Hmmm, that doesn’t make sense as flow through a given orifice should increase with a rise in the pressure drop. If your tank is running out that should lower your pressure drop. Maybe these regulators are designed to require a minimum pressure differential across them. That’s unusual though.
Drop me a message if you need needle valves. I can check to see if I can get them any cheaper.
October 21st, 2008 at 4:52 pm
I haven’t a clue with this stuff, m@. The two URLs I referenced above have some folks talking more in depth. I’ll let you know about the needle valves if I have another dump. Thanks!
October 22nd, 2008 at 5:12 am
Nice article. Thanks. 🙂 Eugene
May 9th, 2009 at 12:05 am
what did you do?
May 9th, 2009 at 8:07 am
Thick, so far I just upped the pressure as recommended in that plantedtank thread in comment #5. So far, so good.
October 10th, 2014 at 8:14 pm
Would having a dual stage regulator prevent dumping?
October 11th, 2014 at 10:50 am
Justin, yes, the dual stage regular does prevent dumping.
March 16th, 2022 at 2:46 pm
This dump never happens with regulators gas heaters or aqualungs they just run out. I have seen people setting up systems on youtube and some have had the needle valve wide open and were useing the regulator knob to control the bubble count. I use a refilled fire extinguisher that has a tube that reaches tonthe botton of the tank, the low pressure set at 50psi and the needle valve the bubble count. The pressure at eot never exceeds the valves ability to control the flow