"Allan" wrote in message
news:MPG.1bf8a99e24d8b458989682@news-server...
I have a 6'x2'x2' tank and sump that holds probably around 180 total
gallons of water. My tapwater is initially around 3 dKH and about 7.6 pH
(tested using Aquarium Pharmaceuticals tests). I added a couple
tablespoons of baking soda to raise the carbonate hardness to 6 dKH.
I have a very similar setup -- 6'x2'x2' open top tank, with little surface
movement. My KH is at 4.5 dKH.
I got a JBJ combo regulator, solenoid, needle valve, check valve, &
bubble counter in the mail on Monday and attached it to my 10 lb CO2
tank. The high pressure gage read 800 psi (is this the normal reading
for a full tank?).
Seems low. The pressure of liquid CO2 at room temperature (below 30C)
is 60bar, which is 870psi. Possibly, your tank wasn't fillled? Note that you
cannot use pressure to tell how full a CO2 tank is because the pressure stays
exactly at 60bar until the tank is almost empty and there is no more liquid
CO2 left. If you want to know whether you have a full tank, weigh it empty
and again after a refill.
I ran about 12 inches of vinyl tubing (I know this is not ideal, but it
is a temporary solution until I can get some CO2 tubing or some Tygon R-
3603 tubing) to my CO2 reactor (CO2 & water entering the top, cascading
over bio-balls, and out the bottom back into the sump).
The losses through vinyl tubing are grossly exaggerated, IMO. The only place
where CO2-proof tubing is useful is between the bottle and the solenoid
(assuming that your solenoid isn't attached directly to the regulator). That's
the high-pressure part of the system, and you might notice a bit of loss there.
For the low-pressure part (following the needle valve), any odd tubing will do.
There were no
bubbles coming out of my reactor, so I'm assuming 100% of the CO2 that
made it to the reactor was diffused.
This sounds like you have an Aqua-Medic Reactor 1000 (or similar):
http://www.marinedepot.com/md_viewIt...7531&ast=&key=
If so, you can be sure that you have 100% diffusion -- those reactors work
extremely well.
I started bubbling at one bubble per second. and let it run through the
night. The next morning, my pH had not moved. I kept increasing the
bubble rate until it was going too fast for me to count (5 to 10 bubbles
per second!). After doing this a couple of days, my pH had only lowered
by 0.2 or 0.4 to around 7.2. The pressure on my tank had dropped by 300
psi so I scaled the bubble rate back to one per second. This morning, my
CO2 tank was flat empty.
I'm finding it impossible to believe that could have emptied out 10 pound tank
this quickly, unless you have a leak. So, first, check whether your tank was
actually full. (Given that you read 800psi instead of 870psi, I suspect you
may have started with a nearly empty tank.) Next, take a spray bottle, put
in a little bit of water and a few drops of detergent, and spray the the
various
parts of your system. You will see bubbles if you have a leak.
Now, I'm assuming that I have a leak somewhere so I am switching to
silicone tubing over vinyl for now and I'm replacing the teflon tape on
the tank threads to the yellow stuff that's supposed to be for gas
connections and test for leaks with a soap solution, but I'm still
baffeled as to why I had to inject so much CO2 to barely budge my pH
levels. I confirmed the CO2 was making it into the reactor and I tested
the pH with water from the tank as well as water from the sump with no
difference. Is my pH test bad? My plants are turning brown and dying, so
I'm assuming the CO2 is not helping much (if any).
If you want to control the CO2 content to any degree of precision, an
ordinary indicator pH test is too coarse, IMO. At least, I can't tell the
difference between 6.6 and 6.9 with any real reliability, but that's a
big difference in terms of CO2 content (too much vs too little). A better
option is to get a electronic meter. These are precise to withing +- 0.01
degrees after calibration.
BTW, I keep my tank at 20-30ppm CO2 permanently (using
a pH controller). A 1.5 kg tank of CO2 lasts me about 3.5 months,
so your 10 lb tank should last you about a year.
Cheers,
Michi.
--
Michi Henning Ph: +61 4 1118-2700
ZeroC, Inc.
http://www.zeroc.com