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finally, my CO2 setup has just arrived!

i can't wait to get my tank filled up and start everything up. just one more question: in what order do i start things up? i assume i connect everything together first - connect the valve to the tank, fill the bubble counter up with water and connect that to the valve, run a line from the bubble counter to the reactor, put the reactor underwater with the powerhead attached. but then what? do i start the powerhead first? what about plugging in the solenoid? and when do i finally open the valve and let the gas start flowing?

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Back in the saddle!

Hi,
I hope there is a communications problem and your terms.
"Connect the valve to the tank?"

If you have a bottled system, you should have a regulator
with gauges that has two knobs on it, a reactor, a one way
check valve, and a bubble counter. The solenoid is optional
and may, or may not be used. You also should have some way
to monitor the pH of the tank.

Steps:
1. Wrap teflon tape (Plumbers tape) around the threads of the
CO2 tank. Just a time or two around the threads. This makes
a good seal preventing leaks, and dammage to the brass
threads.
2. Attach the regulator, so that when the tank is
permanently placed ON THE FLOOR, the gauges are easily seen.
CO2 tanks, if they fall over and the regulator is knocked
off can become small rockets capable of going completely
through brick walls. Be sure the tank is secured it the
upright position.
3. Attach the CO2 tubing to the regulator, and run the
tubing up to the top of the tank where you will mount the
bubble counter. Before the bubble counter, install the
one way check valve. This valve is very important. It
keeps the aquarium water out of the regulator, and tank
should the gas be completely exhausted and a vacuum form.
Every check valve will have the direction of gas flow
stamped on it.
4. Fill the bubble counter with water and connect the
hoses. The hose from the regulator goes to the longer of
the two connections.
5. Mount the reactor and then connect the hose from the
short side of the bubble counter. Connect the hose(s)
from the power head to the reactor, and if it is external
the hose from the reactor back to the tank.
6. Start the power head and have water circulating through
the reactor.
7. Check to be sure that the needle valve on the regulator
is closed. Screwed in very snugly. Be sure the regulator
valve is open. Backed out (CCW) till you do not sense the
resistance of the spring inside the regulator.
8. Open the tank valve completely.
9. Adjust the regulator valve for about two pounds on the
gage
10. Open the needle valve, slightly, while watching the
bubble counter. To start, set the needle valve for about
1 bubble/second.
11. Monitor your pH constantly to see how far it drops.
You do not want to stress your fish by dropping it more
than, say, .2 or .5 over a 24 hour period. Slowly
over a few days, by adjusting the needle valve, bring
the pH down to your desired level.
If you do not already have one, I would highly recommend
the purchase of an electronic pH monitor, place its probe
in the tank somewhere, and leave it there, taking it out
only to clean the head of the probe. I purchased mine
from Drsfostersmith. It is a "Pinpoint" brand and runs off
a 9 VDC battery.

Note, if you have the solenoid, that goes between the
regulator and the bubble counter, and is wired to a timer
so that the gas is turned on during the time the tanks
lights are on, and off during the time the lights are
turned off.
If you are using a controller, then it has an input for the
pH probe, and a place to set the desired pH. It also has
a connection for the solenoid. As long as the pH is above
your setting, then the controller will hold the solenoid
open and gas will flow into the bubble counter to the
reactor. When the desired pH is reached, then the
controller will shut off the solenoid, and stop the flow
of gas.

Hope this helps...
Frank


Last edited by FRANK at 14-Jan-2005 17:19

Last edited by FRANK at 19-Jan-2005 09:33

-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--

thanks, Frank. and YES, it was just a communications problem, a mix up with words. i guess i referred to the regulator as a "valve" because it has a needle valve for adjustments on it. as always, your advice is well appreciated

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Back in the saddle!

With proper water circulation, O2 levels will not drop appreciably overnight.
Although I've seen reports on APD where someone's fish were distressed,
presumably by a lack of O2, I've never seen this confirmed by anyone who paid
the least bit of attention to what was going on. I would attribute these
reports to a newbie hacking around with CO2 and water chemistry and water
movement (creating generally horrible conditions in the tank) and then
blaming the problems on CO2 injection.

In our one tank with manual CO2 injection running continuously, we would
see O2
saturation vary from around 120% in the evening to 90% in the morning
before the lights came on. Given that you can generally only achieve 95% O2
saturation even with the best airstones running full blast, going "down" to
90% at night isn't all that much of a drop.

Remember, there is no relation between the amount of O2 and the amount of
CO2 in the water (within reason). The O2 level in the water is determined
by diffusion at the water surface, proper circulation (mixing surface water
and lower water), the amount used by the aquarium bio-life and the amount
contributed by photosynthesis. Turning off CO2 at night does nothing to
prevent O2 from dropping. O2 is going to drop when the lights go out since
the plants stop photosynthesizing.

Your fish are going to get stressed only if CO2 increases TOO much
overnight or
the O2 is reduced TOO much overnight. Even with high oxygen levels, fish
cannot
respire CO2 unless the concentration of CO2 in the water is less than the
concentration of CO2 in the fishes blood. The exchange of O2 and CO2 in the
gills is determined by the relative concentration of each gas on both sides
of
the gill membrane and the exchange of each gas at the membrane is
independent of the other.

Many people miss this point. With high O2 AND high CO2 in the water, CO2
cannot
leave the blood (meaning O2 can't enter the blood; they bind to the same
site on the hemoglobin molecule) and the animal asphyxiates. With low O2
AND low CO2 in the water, CO2 can leave the blood but O2 can't enter and
the animal
asphyxiates.