Any cons to dropping some dry ice in your pool for visual effects? (Halloween party Friday)


Todd....

Oh yes. Remember, dry ice is carbon dioxide in its solid state. CO2 is a functional acid in your pool water and can lower your pH fairly drastically, resulting in some serious water balance issues. I would advise to not put dry ice in your pool.

Thats what I needed to know, thanks!


Todd....

...but what a cool idea. If only we had some sort of resident Chemistry Geek to tell us exactly what harm would come of such a thing.

Been there and done that as shown/described here. I didn't take pictures of what happened in the pool, but I do describe it including the effects on pH.

As for the effects on global warming, figure that a typical car outputs about one pound of CO₂ per mile.

Richard

So that being the case, I say go for it. Drop the pH a little. Fix it saturday. Pools are for enjoying.

Somebody did it and put a vid on Youtube...



And here's the link to the video... http://www.youtube.com/watch?v=uhXA9ON6igk

Have fun,
Adam

Putting a small amount in a pool is one thing, but adding a bunch to a spa will lower the pH dramatically and could very well damage equipment. Adding even one pound of dry ice to a 350 gallon spa can lower the pH to 5.5 and ten pounds to 4.6.

You could also fill a 5 gallon bucked with pool water almost to the top and sink it on one of your steps with the rim just above waterline. Add the dry ice the the bucket water and the smoke will pour out over the pool surface.

I would also warn to be very careful in an enclosed space with it. Carbon Dioxide is actually toxic, at lower then you would expect levels. That guy in the video link who jumped in the spa with it was probably being much more risky than you would think, plus that looked like an enclosed room. A little bit as party favours isn't a big deal, but when you are throwing 60 lb blocks into hot water, then sticking your face in the vapour, not a good idea.

Our teenage daughter hosted a Halloween party last night. After reading this and other threads, I calculated our pool could handle about five pounds of dry ice. My wife picked it up Friday afternoon. It was pelleted, rather than in a block. We tossed it in to great effect and enjoyment by all. Later I asked my wife how much she had bought. Ten pounds. Soo, about seven and a half pounds of Borax later, I think we're back to around pH 7.2. Ah life.

Mother Nature also added to our decorations. We had our first real rain after our Mediterranean-style dry summer on Friday and six salamanders emerged and decided our pool would be a great place to hang out this winter. So we had a dozen eyes of newt in our witches' brew! (They seemed to survive the festivities and were quite lively when I fished them out today.)

I dont think putting blocks of it in there would be a great idea!

What if I actually need to lower pH? Would this be a good substitute to adding muriatic acid? I live near an ammonium nitrate plant that produces copious amounts of dry ice as a byproduct and they sell it cheap.

CO2 systems are sometimes used in commercial pools to lower the PH. See this topic for a little more discussion of the subject.

We have been discussing this same video over in the Coffee Bar section. I raised the same question about using it in place of Muriatic Acid too. Check the thread out over here

We've put about 5 lbs of dry ice in our pool during a party and it didn't affect pH much. Of course there was a lot of splashing around that may have outgassed it quick. Ventilation is very important.