Lowering pH with CO2

[mas985]

So does that mean it would take about 5 oz of dry ice?

That would be interesting to compare cost to acid. Storage would be an issue but if you can get it cheap enough, then losing a little might not matter.

[mas985]

Just found this:

http://dryicedelivered.safeshopper.com/4/cat4.htm?299


25 lbs for $40 delivered. So that is 80 doses for $.50 per dose. Muriatic is about 8 oz for a .2 PH change or 16 doses per gallon @ $8/gallon or $.50/dose.

Oh well.

[aquarium]

25 lbs for $40 delivered. So that is 80 doses for $.50 per dose. Muriatic is about 8 oz for a .2 PH change or 16 doses per gallon @ $8/gallon or $.50/dose.

Oh well.

One gallon of muriatic here costs only $3, so the comparison is even worse.

[mas985]

One gallon of muriatic here costs only $3, so the comparison is even worse.

Yes you are right! I pay 8$ / 2 gallons not 1 so it would be $.25 / dose. Much better than dry ice. My bad.

[tagprod]

Just found this:

http://dryicedelivered.safeshopper.com/4/cat4.htm?299


25 lbs for $40 delivered. So that is 80 doses for $.50 per dose. Muriatic is about 8 oz for a .2 PH change or 16 doses per gallon @ $8/gallon or $.50/dose.

Oh well.

Muriatic acid isn't 8 dollars a gallon where I live - It's closer to $5

[chem geek]

So does that mean it would take about 5 oz of dry ice?

Yes, you are correct. But as your later post showed, it isn't more economical than Muriatic Acid and storage would be a bear, requiring one of those special high-efficiency thermos-type containers. Kind of interesting how the prices worked out to be similar. Thanks for doing that research.

Oh yeah, as for lowering the pool temperature, this would be pretty negligible for the amount that would be added to the pool. Dry ice is no warmer than about -109F or -79C but even if it were colder than that, the amount would hardly budge the pool temperature. One gallon of some substance that was even at absolute zero (which is impossible and is about -460F or -273C) mixed with 10,000 gallons of pool water at 80F would only lower the temperature by 0.05F or less than a tenth of a degree (assuming similar heat capacities for water and the substance, but even with a typical difference, we're still not talking about a large shift in temperature).

[CarlD]

To the China Shop with this thread!

I cannot recommend Dry Ice to lower pH!

It's an interesting intellectual exercise, but not practical.

[Jakebear]

Wow I'm doing pretty good --- I think that makes 4 posts that I started that got moved here Ben really needs to create the Geek page.

Richard, Thanks for the physics lesson (thought you were a chemist ). I don't know why but I thought CO2 was colder but like you say the proportion is so wide I can understand the minimum temp loss.

In my previous lifetime I worked the meat processing industry. We used liquid CO2 in the process. Stored in a non-refrigerated or insulated tank. When it came out the pipe it turned to CO2 snow. -- I suppose that would be a delivery method rather than cakes at atmospheric pressure.