Automatic or manual co2 injection

I'm thinking the automatic might be more trouble than its worth. probe
replacement, calibration, sticky valves.

If my kh is 8dh, I'm thinking of just bubble in some co2 slowly untill
my goal ph is reached, make sure co2 isn't too much, and leave it on
all the time. I would think turning the manual system off at night
would cause ph up and down?

It seems to me (guess) that the automatic system might be on most of
the time anyway.

*if* the tank paramaters remain *fairly* constant I would think the
amount of injected co2 would remain fairly constant also?

Thank you all for the help

IMO automatic is the way to go. The controllers & probes are much better
than they used to be. I know people that only calibrate the probes once
every 4 months & they are hardly out. Never seen a sticking valve.

Even with a manual system on all the time you are going to get PH swings
because you are putting CO2 into the tank at night & its not being used by
the plants. Not to mention the plants are giving off CO2 at night.
wrote in message
oups.com...
I'm thinking the automatic might be more trouble than its worth. probe
replacement, calibration, sticky valves.

If my kh is 8dh, I'm thinking of just bubble in some co2 slowly untill
my goal ph is reached, make sure co2 isn't too much, and leave it on
all the time. I would think turning the manual system off at night
would cause ph up and down?

It seems to me (guess) that the automatic system might be on most of
the time anyway.

*if* the tank paramaters remain *fairly* constant I would think the
amount of injected co2 would remain fairly constant also?

Thank you all for the help

http://www.aquabuys.com/page/aqb/PROD/i2/co2_set_dlx_05

Any good? I like the external reactor. I might use my Ehiem 2013
canister filter as a reactor?

I guess if I were to get a controller I would like a *good* one

Thanks

Here ya go.

http://cgi.ebay.com/SMS122-JBJ-Co2-R...cm dZViewItem


wrote in message
oups.com...
http://www.aquabuys.com/page/aqb/PROD/i2/co2_set_dlx_05

Any good? I like the external reactor. I might use my Ehiem 2013
canister filter as a reactor?

I guess if I were to get a controller I would like a *good* one

Thanks

wrote:

I'm thinking the automatic might be more trouble than its worth. probe
replacement, calibration, sticky valves.

Quite possible.


If my kh is 8dh, I'm thinking of just bubble in some co2 slowly untill
my goal ph is reached, make sure co2 isn't too much, and leave it on
all the time. I would think turning the manual system off at night
would cause ph up and down?

It seems to me (guess) that the automatic system might be on most of
the time anyway.


Depends on where you set the needle valve. If it set for a low flow
rate then the valve-open time will be longer.


*if* the tank paramaters remain fairly constant I would think the
amount of injected co2 would remain fairly constant also?


Yes.

CO2 is lost at the surface of the water. The amount depends on how
tightly closed the tank is, and how much rippling of the surface there
is due to pump circulation. In many (probably most) cases this loss
will exceed what is being used by the plants, so the change in demand
with plant density or lighting becomes a secondary factor. The loss to
the air is constant, thus a constant flow rate of CO2 will produce a
nearly constant concentration of CO2. You can check this yourself by
testing morning and evening. In my experience with a specific 125G
tank, the results did not differ more than experimental error in
reading pH and KH.

As far as pH swings, the rate at which CO2 concentration changes in the
tank is quite slow. It takes hours to reach equilibrium after making a
flow adjustment. I believe that the fish are not sensitive to this at
all. The many ills said to be due to pH swings are more likely due to
changes in mineral concentrations, which are not much affected by the
CO2.

One reason that many people cite for using the pH controller is that
they have difficult to adjust needle valves. A controller is a very
expensive and imperfect alternative to a good needle valve. However,
for the smaller aquarium with lower demand the issue is real. Another
issue is the "end of tank" dump, a temporary increase in pressure and
flow for the last few days of CO2 before the tank is empty. This is a
problem with the small diaphragm, cheap regulators sold for aquarium
CO2. What works well to minimize both problems is to adjust the
pressure up to something easily readable on the gauge, like 10-15 PSI.
(It can take a while for the regulator to settle in after making
adjustments.) The procedure that calls for a wide open valve and then
adjusting flow with the regulator will result in poor stability and
should not be used.

If you would buy a regulator and controller separately, you can try the
regulator by itself for a week or two before taking the plunge for a
controller and pH probes. A good starting point is maybe 1 bubble per
two seconds in a small tank (20G or less) and 1 bubble per second for
larger than that. You can make an adjustment mornings and evenings
until you get to your target, say 15-20ppm. Once you are in that range,
check pH morning and evening for a few days to see if the stability
meets your expectations.
--

wrote in message
oups.com...
I'm thinking the automatic might be more trouble than its worth. probe
replacement, calibration, sticky valves.

If my kh is 8dh, I'm thinking of just bubble in some co2 slowly untill
my goal ph is reached, make sure co2 isn't too much, and leave it on
all the time. I would think turning the manual system off at night
would cause ph up and down?

It seems to me (guess) that the automatic system might be on most of
the time anyway.

*if* the tank paramaters remain *fairly* constant I would think the
amount of injected co2 would remain fairly constant also?

Thank you all for the help


The only manual injection I know of, which you can turn off is a CO2
cylinder. At that point, it might be worth making automatic (depending on
how low your buffer normally is, and how technologically inclined or
accepting you are). To a degree, the carbonic acid's acidification of your
water is self-regulating (because as the CO2 water-air delta rises, the rate
of gaseous exchange increases, trying to equalize it), so in static water
conditions with a reasonable buffer, manually can work very well. Aquarium
water conditions are never completely static ;~), but within a reasonable
range it works. One variable which is a big deciding influence is the
water's natural buffer, which, if low, suggests an automatic system, and if
high, permits a manual system with reduced risk of negative consequences.
However at 8dkH, I think you're neither low enough to worry much, nor high
enough to worry little, so that's no help ;~).
--
www.NetMax.tk

Thinking