View Full Version : Hopefully Last CO2 Question
thadius65
10-04-2006, 8:59 PM
Maybe I should just stick to the computer industry... jeesh this stuff is confusing.
So, no Co2 injected into tank. PH 6.8, kh between 1 and 2. Install of CO2 and PH Controller. PH reads 6.8. After only about 1 hour of 2-3bps of CO2, the PH is 6.4 and holds steady... running calculators (PH/KH relationship) shows a jump from 9ppm to 23ppm CO2. No way that is possible. Buy a Red Sea CO2 in-the-tank CO2 tester. 1ml of water, two drops of "stuff", invert, vacum created, slowly slide down 4"+ into tank keeping vacum. Reading after 10minutes and good for up to a month... Reading after this short period of time is yellow (or + on the marking), indicating to much CO2. No way possible....
Sigh... do I just shut down til I am here all day and do 2-3bps until my fish go to top for air, or ??
Thoughts?
Thanks! -- Ted
MidnightPyro
10-04-2006, 9:19 PM
How big is your tank? 2 bps for about an hour or two puts my CO2 in my tank to about 25 ppm in my 29 gallon. I'd honestly throttle back the CO2 a little bit. Are the fish gasping?
reiverix
10-04-2006, 10:27 PM
only about 1 hour of 2-3bps of CO2, the PH is 6.4 and holds steady... running calculators (PH/KH relationship) shows a jump from 9ppm to 23ppm CO2. No way that is possible.Perfectly possible. When you're pumping the CO2 into your tank it will start dropping your pH very quickly.
I wouldn't bother with an in tank CO2 tester. Even using the pH/KH relationship is not a 100% guarantee of accuracy. It's just not so simple to measure the CO2 content in water without lab gear. I don't even bother trying to measure CO2 with KH. What I do is let pH drop by around one full point. After several hours plants should be noticably pearling, depending on species of course. I've never cranked CO2 up so much that my fish have came to the surface.
What I would suggest though is to raise your KH a little to buffer your water better. Adding some crushed coral to your filter will bring it up a few degrees.
Goatman
10-04-2006, 11:20 PM
Fish gasping? If yes, turn it down, if no, leave it alone...
Plants pearling? If yes, leave it alone, if no, turn it up...
Skip the test kits and indicators... bells and whistles are nothing but extra things to fail. If the system works, why question how well it is working to a quantitative figure?
Be careful John R. I suggested using coral to Ted to buffer up his water and was met with much ridicule for it.:):):)
Ted it seems that there are a few different schools of thought on the pH/kH relationship and I'm still basically in the old school at this point (cause I'm an old guy).
However, now I'm starting to believe that the theory of a 'pH crash' has been a bit over done. But also know that kH has a stabilizing affect on pH and can assure, to some degree, the slow change in pH that is necessary for relieving stress to fish while the hobbiest arrives at his/her optimum levels.
I totally agree with John R. and Goatman with regard to small adjustments and observing the plants and fish for reaction.
Len
reiverix
10-05-2006, 11:19 AM
I have read some articles lately about a KH value of 1dH being sufficient, as long as it is replenished with weekly water changes. I guess there's no harm in adding crushed coral if only to feel safer about it, although I do feel it helps the snails build better shells. The acidic properties of CO2 can be quite harsh.
loaches r cool
10-07-2006, 12:41 AM
I only run about 2bps on my 75 and get good co2 levels, I dont test it alot with kits and I find the ph and kh kits to give you a huge margin for error but last a checked I was getting ~25ppm. Was going to bump it up a bit since many plant keepers say they run around 35ppm but I just put together a new diffuser so wanted it to run a couple weeks to see the difference before changing the bps rate.
fresh_newby
10-09-2006, 12:03 PM
Fish gasping? If yes, turn it down, if no, leave it alone...
Plants pearling? If yes, leave it alone, if no, turn it up...
Skip the test kits and indicators... bells and whistles are nothing but extra things to fail. If the system works, why question how well it is working to a quantitative figure?
well put
Ted....answered in the other forum...check it out :)
http://www.plantedtank.net/forums/plants/36062-hopefully-last-co2-question.html
fresh_newby
10-09-2006, 12:21 PM
Us old dogs can learn new tricks too.....We just try to keep an open mind...<that is, with everything but rap> lol :duh:
Be careful John R. I suggested using coral to Ted to buffer up his water and was met with much ridicule for it.:):):)
Ted it seems that there are a few different schools of thought on the pH/kH relationship and I'm still basically in the old school at this point (cause I'm an old guy).
However, now I'm starting to believe that the theory of a 'pH crash' has been a bit over done. But also know that kH has a stabilizing affect on pH and can assure, to some degree, the slow change in pH that is necessary for relieving stress to fish while the hobbiest arrives at his/her optimum levels.
I totally agree with John R. and Goatman with regard to small adjustments and observing the plants and fish for reaction.
Len