Gandalf? Dumbledore? Merlin? Great guys!

But we don't need them here for our pool chemistry. It's all really simple and made complex for rather nefarious reasons:

Our methods, if adopted universally throughout the US and Canada (where most of our members our), would shatter revenues for the big pool chemical companies.

We recommend bleach for chlorine, but at the moment, we are holding back on recommending Chlorox brand since they added a "whitener". It may be this is actually a good thing and Chlorox has made some noises to that effect, but even so:
Bleach instead of Tri-chlor, Di-chlor, Cal-Hypo--Only Buckman selling liquid chlorine wouldn't be hurt.
Brands like HTH (Arch Chemicals ) currently have NO products that I can personally recommend, since they dropped the 5-Way test kit.

BioGuard sells ordinary chemicals you can buy in the grocery store at insanely high prices--Paying for packaging and labels.

They all sell chemicals and push chemicals you don't want or need. Look how many threads we have of people converting from Bacquacil. Bac is really good for company and pool store profits, but the number of people here who like and prefer it (and I'm not knocking them at all--I don't argue with success) is far smalled than those complaining--1:10 maybe.

Most pool stores sell Nature2 systems as if they were a product that had a scientific basis for usage. I view N2 as snake oil, personally.

So what I'm getting around to with this rant, is that "magic" is what is necessary to keep the profits of the pool chem people up, the BioGuards and Archs. Without it, they are forced to offer truly price-competitive products. Knowledge by pool owners is a threat to them. Just one last example: Recently, HTH (the Arch brand), started manufacturing their Tri-Chlor pucks loaded with copper. Most Tri-Chlor pucks don't have copper. Copper in your water is usually a bad thing--it turns blonde hair and nails green and shouldn't be ingested. But HTH is now adding it SOLELY so they can print on the label "Now-Double Acting!" because copper is an algaecide.

Doesn't matter that it's a bad thing--what matters is it can be advertised as "double acting". And consumer ignorance is vital to the campaign's success.

Pool volume: The only thing I can suggest is you have to break your pool down into simple shapes for which the volume forumlae are known. A sphere's volume is 4/3 pi*r cubed. If your pool's deep end approximates half a sphere, you can compute that part.

Simplest example: An oval pool of a constant depth: 18x33x4: An oval is a rectangle with a semi circle at each end. So the 18x33, MUST have half an 18'diameter circle at each end--or one 18' circle.

The radius of these is 9', so you have 9' to subtract from each end to get the rectangle in the middle--33-(9+9)= 15 '. So you have an 18x15 rectangle, and an 18' diameter circle, both 4' deep. The rectangle is 270 square feet, the circle is pi*r squared, or pi*81= aprox 254 sq ft. Together that's 525 sq feet, times 4' (the depth) for 2096 cubic feet. Each cubic foot contains 7.48 gallons, so an 18x33x4 pool contains 15678 gallons, approximately, or 15,700 for rounding.

You have to use the same breaking down for your pool, a lot more shapes, more difficult to figure, but the method's the same. Hope this helps.