At what PSI should I refill my CO2? - The Planted Tank Forum
LinkBack Thread Tools Display Modes
post #1 of 9 (permalink) Old 03-27-2013, 06:07 AM Thread Starter
Algae Grower
Join Date: Sep 2007
Location: Austin, TX
Posts: 70
At what PSI should I refill my CO2?

I'm on the first fill of my 10 pound CO2 tank. It was about 1000 PSI when I got filled and it quickly dropped to 900 PSI. It stayed around 900 for about two months. Over the last week, it has dropped to 600 PSI.

At what point do I get a refill?
leros is offline  
Sponsored Links
post #2 of 9 (permalink) Old 03-27-2013, 06:17 AM
Planted Member
Join Date: Aug 2010
Location: sf
Posts: 276
you might have a leak somewhere. if you have a 10LB tank, it should last you more. refill when no co2 comes out if you have a dual stage regulator.
mwuf15 is offline  
post #3 of 9 (permalink) Old 03-27-2013, 06:35 AM
Planted Tank Obsessed
Join Date: Apr 2012
Location: Los Angeles, CA
Posts: 403
What's your bubble rate? A 10# tank should last several months at least on a small to mid sized aquarium. If it's at 600 psi, it means there's no more liquid CO2 left and you're just running on pressurized gas. I'd get it refilled now, especially if you have a leak.
TwoTacoCombo is offline  
post #4 of 9 (permalink) Old 03-27-2013, 09:31 AM
Darkblade48's Avatar
Join Date: Jan 2008
Location: Toronto/Singapore
Posts: 9,870
As already mentioned, unless you are running your CO2 cylinder on a large aquarium, you most likely have a leak, as 2 months is quite a short time.

I would refill your cylinder (especially if you are using a single stage regulator) and also take some time to check for leaks (use soapy water).


A Primer to Pressurized CO2 and A Primer to Planted Tanks
Eheim Pimp #362 - Eheim 2213 x2, Eheim 2028, Eheim 2217, Eheim surface skimmer and Eheim autofeeder.
Victor Pimp #33 - HPT272-125-350-4M
Darkblade48 is offline  
post #5 of 9 (permalink) Old 03-28-2013, 12:51 AM
Wannabe Guru
flight50's Avatar
Join Date: Apr 2012
Location: dfw
Posts: 1,364
It depends on the regulator and what your bubble rate is set to in my opinion. 2 months could be fine with a high bubble rate. I had a 5lb with an electronic regulator that normally goes 1-1/2-2 months at 2-3 bubbles per second. It can go to 0 and doesn't dump before reaching 0. Before I upgraded to an electronic regulator I had to change my tank once the psi dropped to 3-400 psi otherwise it would dump. I found out the hard way and killed half my tank before noticing it dumped.

Check for leaks, use soapy dishwashing liquid around all connection. if no bubbling occurs you have no leaks, then it is what it is. Not all regulators are built the same. Experiment with your tank and monitor it. It was difficult for me to remember to monitor so I went with an electronic regulator. It was more expensive but it was the best investment I have spent on my equipment by far.

Eheim Pimp #509
Finnex Club Member #31
The Fraternity of Dirt #146

Builds - DIY Quad 40g Stands & 90g Stand
Planted Tank Journal
flight50 is online now  
post #6 of 9 (permalink) Old 03-28-2013, 02:57 PM
Join Date: Dec 2012
Location: Rochester, NY
Posts: 3
when co2 is compressed, it becomes a liquid. if you hold the tank horizontally, and slowly rock it end to end, you can feel the liquid.when a tank is full, the psi could be anywhere from 800-1000 depending on outside temp. when it gets below that it is time for a refill.
Soupy944 is offline  
post #7 of 9 (permalink) Old 03-28-2013, 03:35 PM
Planted Tank Guru
HD Blazingwolf's Avatar
Join Date: May 2011
Location: Chattanooga, TN
Posts: 4,907
i refill mine when it drops below its liquid pressure
at my house temperature its right about 800 psi
when i see the needle drop,. its fill time.. Take into account that after a refill, the tank needs about 24 hours to adjust to room temperature. you'll see the pressure change during this time

as other's have said u may or may not have a leak. my 20 lb lasts 6 weeks on my 75 gallon, and i have no leaks. just lots of waste
HD Blazingwolf is offline  
post #8 of 9 (permalink) Old 03-28-2013, 08:44 PM
Planted Tank Obsessed
WheeledGoat's Avatar
Join Date: Mar 2013
Location: Chicago
Posts: 324
you could also go by weight - I've got the numbers written down at home for both my 5# and 10# tanks - empty & full weights. it's a little bit of a pain to unhook to weigh but at least you have an accurate idea of where you're at!

(this was more important to me before hosting a party to know I wouldn't run out of co2 to dispense my kegged beer... but perhaps knowing your aquarium won't go without co2 when you're on vacation??)
WheeledGoat is offline  
post #9 of 9 (permalink) Old 03-28-2013, 09:56 PM
Planted Tank Guru
talontsiawd's Avatar
Join Date: Oct 2008
Location: Concord, CA
Posts: 4,562
Send a message via AIM to talontsiawd
As said, sounds like you have a leak. My 5 lb on my 20 gallon lasted me about 3 months with a leak. My 20 lb on a 29 could last me over a year. It depends on how much you are injecting/loosing but I would check for leaks.

As for PSI, once you get it at a fairly constant temp by having it at your house, it will stay at a certain PSI, around 800, but depends on temp. It will stay at that until it's emptying out the last bit. So after it starts dropping, it's time to refill.
talontsiawd is offline  

Quick Reply

Register Now

In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome