I recently added a pressurized CO2 system to my 38 gal aquarium. I use
RO water and added calcium carbonate to obtain 4 KH and 4 dGH. The pH
initial shot up to 8.5 (from 7.2) and then dropped to 7.6 overnight.
When I got home from work it was down to 7.4 and has not moved in the
16 hours since then. Is this typical?

Here is the system:
Aquamedic CO2 Reactor 500
Milwaukee SMS122 pH Controller
Milwaukee MA957 Regulator
Eheim 2011 to provide the current

The 2011 and an additional 2213 are using 2 Eheim surface extractors.
Neither filter's discharge is directed at the surface. There are no air
stones either. So there should not be much CO2 stripping going on. I'm
using a 96wt 5700K compact light and the tank it moderate to heavily
planted. Substrate is a quartz sand/laterite mix.

Is there any obvious reason the pH is being so stuborn?

"jet" wrote in message
oups.com...
I recently added a pressurized CO2 system to my 38 gal aquarium. I use
RO water and added calcium carbonate to obtain 4 KH and 4 dGH. The pH
initial shot up to 8.5 (from 7.2) and then dropped to 7.6 overnight.
When I got home from work it was down to 7.4 and has not moved in the
16 hours since then. Is this typical?

Here is the system:
Aquamedic CO2 Reactor 500
Milwaukee SMS122 pH Controller
Milwaukee MA957 Regulator
Eheim 2011 to provide the current

The 2011 and an additional 2213 are using 2 Eheim surface extractors.
Neither filter's discharge is directed at the surface. There are no air
stones either. So there should not be much CO2 stripping going on. I'm
using a 96wt 5700K compact light and the tank it moderate to heavily
planted. Substrate is a quartz sand/laterite mix.

Is there any obvious reason the pH is being so stuborn?

Your description seems to have the answer

The calcium carbonate is diffusing faster because of the carbonic acid
coming from the CO2. 7.4 is probably the balance between the carbonic acid
and calcium carbonate. As the calcium carbonate levels drop, so will the pH.

How is your hardness dealt with? Are you adding powdered calcium carbonate,
or do you filter over coral or something?

If you are adding by hand then 7.4 looks like it will be about where your
CO2 pH will be. If it's a more sedentry type of buffering, then as it
weakens over time, so the pH, buffering and hardness will drop. Be careful
of pH crashing in any case.


Oz

--
My Aquatic web Blog is at http://members.optusnet.com.au/ivan.smith

I used powdered calcium carbonate. There is no more obvious residue
left in the tank, so hopefully it is as hard as it will get. I expected
to get a higher CO2 levels than this. At 4 KH and 7.4 pH I'm only
getting 4.8 ppm of CO2.

I need to come up with a better way to add the powder at the next water
change. I'm thinking of branching a line off one filter return and
running a very low flow through a bottle DIY reaction chamber with the
calcium carbonate in it. This should eliminate the large swing of
adding the unbuffered powder all at once. It will also give me a bit
more control over the hardness. I can't see going though this bit every
water change as the CO2 tries to catch up with the carbonate.

In article .com,
says...

I used powdered calcium carbonate. There is no more obvious residue
left in the tank, so hopefully it is as hard as it will get. I expected
to get a higher CO2 levels than this. At 4 KH and 7.4 pH I'm only
getting 4.8 ppm of CO2.

I need to come up with a better way to add the powder at the next water
change. I'm thinking of branching a line off one filter return and
running a very low flow through a bottle DIY reaction chamber with the
calcium carbonate in it. This should eliminate the large swing of
adding the unbuffered powder all at once. It will also give me a bit
more control over the hardness. I can't see going though this bit every
water change as the CO2 tries to catch up with the carbonate.



Get a new Rubbermaid garbage can and put your new water for the water
change in it. Add your chemicals and a heater and a power head to mix
the CC into the water. I do this 24 hours before the water change and
get the water temp to match the tanks.

--
Jim Anderson
( 8(|) To email me just pull my_finger

"jet" wrote in message
oups.com...
I used powdered calcium carbonate. There is no more obvious residue
left in the tank, so hopefully it is as hard as it will get. I expected
to get a higher CO2 levels than this. At 4 KH and 7.4 pH I'm only
getting 4.8 ppm of CO2.

I need to come up with a better way to add the powder at the next water
change. I'm thinking of branching a line off one filter return and
running a very low flow through a bottle DIY reaction chamber with the
calcium carbonate in it. This should eliminate the large swing of
adding the unbuffered powder all at once. It will also give me a bit
more control over the hardness. I can't see going though this bit every
water change as the CO2 tries to catch up with the carbonate.


I consider myself very lucky in the light if what you are going through. The
water out of the tap here already has a high buffer and pH
(10dGH/10dKH/7.4pH), so I don't have to really mess with it on the "hard
side".

I use 2 X 2L yeast powered (500g(2 cups)Raw Sugar, 1.5 tsp bakers yeast,
1.5tsp Baking Soda) CO2 reactors on a 220L (55Gal) tank. The bottles are
alternate cycled (change one bottle each week) to stop massive fluctuations
in the CO2.

My hardness is 10dGH/dKH and the pH is a pleasant 6.8 ~7.0 doing it this
way.

The CO2 diffuser area has seen a few things from bio-ball filled tubes, to
passive bell, inlet injection on the canister filter and currently I'm
having great success just by passing the 2 bottles through a water bubble
counter (acts as a backflow/siphoning prevention and carbonic acid buffer as
well) and then passing that to the venturi input of a powerhead near the
outflow from the main filter.

The bubbles come out fine and are rolled and smashed along the back pane of
glass. I wouldn't have thought this would work well but I must be getting
sufficient CO2 because the plants pearl almost every day. CO2 is part of the
pearling, and good fertiliser is the other part.

As long as you sort your buffering out and settle on a CO2 system I can see
you having masses of healthy plants very shortly

Oz

--
My Aquatic web Blog is at http://members.optusnet.com.au/ivan.smith

I suppose I could put in a bell and fill it with CO2 to get that
started. hmmm...

Ozdude wrote:

I consider myself very lucky in the light if what you are going
through. The
water out of the tap here already has a high buffer and pH
(10dGH/10dKH/7.4pH), so I don't have to really mess with it on the
"hard
side".


Must be nice. The tap here is over 20dGH with almost no carbonate
hardness, so even dilution requires that I add carbonate.

I'd forgotten how much patience this takes.

Tonight the carbonate hardness is up to 5 KH but the pH is down to 7.2.
Probably be another day or two before it gets to the 6.8 set point.

If this helps, I was using powdered calcium carbonate but was recently
referred to liquid calcium carbonate. It's a lot easier and the results are
pretty instant. I added 5mls to a 200litre tank and the KH went up 1degree
when I tested straight after. It's called PH booster (make sure you get the
calcium carbonate one, not the phosphate one)

Justin.

"jet" wrote in message
oups.com...
I used powdered calcium carbonate. There is no more obvious residue
left in the tank, so hopefully it is as hard as it will get. I expected
to get a higher CO2 levels than this. At 4 KH and 7.4 pH I'm only
getting 4.8 ppm of CO2.

I need to come up with a better way to add the powder at the next water
change. I'm thinking of branching a line off one filter return and
running a very low flow through a bottle DIY reaction chamber with the
calcium carbonate in it. This should eliminate the large swing of
adding the unbuffered powder all at once. It will also give me a bit
more control over the hardness. I can't see going though this bit every
water change as the CO2 tries to catch up with the carbonate.

Who is the manufacturer?

Nutrafin make it and it's exact name is PH stabilizer KH booster.

"jet" wrote in message
oups.com...
Who is the manufacturer?

It seems to have settled down to around 6.9 pH with a lot of pearling
(looks a bit like someone filled the tank with soda water, which I
guess I have). I have a powerhead in the tank that must be removing CO2
because when it is on the pH goes up to around 7.2. No obvious surface
agitation, but there must be enough for this to happen.