On Wed, 21 Jan 2004 20:13:52 UTC, "Nemo" wrote:

Does anyone have experience with SeaChem Acid Buffer and Alkaline Buffer?

I know this goes against the established wisdom in this hobby, but I
maintain my swimming pool water chemistry using chemical additives (ph, kH,
gH, and sanitizer). Why is it difficult to achieve a stable chemistry in a
FW tank with additives as well?

Do you really check both pH and KH in the pool? And what values do you get
a few days after you add the proper additives to the pool?


...[snip many frustrating experiments!]
I dosed for 6 dkH, 6dH, and a pH of 6.0. Within 15 minutes, the pH was back
up to 7.2!

Arghhhhhhhhhhh!!!!!!!!

Reading the label on Seachem's Acid Buffer bottle, it says that the product
lowers the pH and produces CO2. Hmmmm, is this * HOW * it reduces the pH? Is
aeration driving the CO2 out thus causing the pH increase?

That's the essentially right answer. The acid buffer doesn't lower pH *by*
producing CO2; it acidifies the water, and that forces more of the total
carbonate (KH) to be carbonic acid -- which, practically, means CO2. Since
you now have a higher concentration of CO2 in the water than in the air,
the CO2 starts escaping -- faster, if you're aerating, but it will escape
anyway. The pH goes back up, and the KH goes down, just as you observed.


I don't know. But the label says that the product should be used in
conjunction with Alkalinity Buffer to produce the desired (stable) pH. But
it mumbles something about adding it directly to the tank for best results .
I DON'T THINK SO !! At least not until I get stable water parameters in a
bucket for a couple of days.

At this stage, I am very skeptical about Seachem claims regarding the
combined use of Acid Buffer / Alkalinity Buffer. The best way to verify,
obviously, would be spend another $20 and try it. But again, the company's
literature mumbles about having to "trial and error" the correct combined
dose. Well, that does not make me comfortable.

So .. does anyone have any success / experience with SeaChem Acid Buffer /
Alkaline Buffer or other similar products? Why is it that pool water can be
balanced but not aquarium water?

Though I've given up on them, buffers will probably work so long as you
forget KH! The theory is that you mix the buffers in the right amounts,
and this holds the pH in place, and then you don't need KH to hold the pH
steady, so you don't care that at pH 7 your KH will be about 1. (Unless
you're raising plants, which care about CO2 levels.)

As charts such as http://www.csd.net/~cgadd/aqua/art_plant_co2chart.htm
show, pH and KH and CO2 have a fixed 3-way relation, and when you hold CO2
to 3-4 ppm (the atmosphere does this for you), the KH and pH have a fixed
relation. Try to force them out of that simple relation, and you're
fighting the atmosphere. We plant-growing, CO2-injection types are
continuously fighting the atmosphere.

As to pool water, I can only guess that it takes a couple of days to lose
excess CO2, and the chemicals get added often enough to counteract that
effect.

--
Dan Drake

http://www.dandrake.com