If you find that you're never quite getting the right effect from your chemistry, then you can start increasing your volume you use for calculations. For chemicals, if you don't put in quite enough, it's pretty easy to just add a bit more the next time you test a couple days later rather than to overdose and have to counteract it with a different chemical. The idea is that a little bit of extra circulation (I mostly deal with VS pumps) is just a slight bit more electricity, but under-circulation is algae and a messy pool. I then round down to the next 5k and use this as the estimated volume for chemicals calculations (under-dose). I round my calculated gallonage up to the next 5k and set my pump speeds and run times based on this (over-circulate). When I'm getting a new pool owner up and running during a pool school, I estimate the pool volume by walking the pool off (my boots happen to be almost exactly a foot long when I walk heel-toe) and checking the depths with a pool pole. I generally run on the principle of 'over-circulate, under-dose'. Honestly though, getting EXACT gallonage is kind of a lost cause. Cubic feet is easy to multiply out with a tape measure, and the magic number to remember is there's 7.48 gallons in a cubic foot. The only other thing that's usually a little different is the walls all typically curve in slightly rather than being flat to the ground, so you probably should subtract a few hundred gallons to get an almost exact number.īreak it into sections to calculate.

There are 7.481 gallons in each cubic foot so you multiply 7.481 x 4,341 and you get 32,475 US gallons.Īll you have to do is change the length and depth of each of those portions to get a very close to accurate number. Do this same thing for any other cut outs from the shape of your pool (like the Roman cut outs), along with benches etc. So take 4,373 - 32 gives you 4,341 cubic feet. Subtract Stairs: Let's say your stairs are about 4ftx8ft and the middle step (average depth) is 2ft. But you need to subtract your stairs and any other cut ins from the shape of the pool. Your total cubic feet is 4,373 cubic feet. This must be 4ft long in this case (because we've already used 33ft of the 37ft pool), and let's say it goes from 5ft to 10ft (average 7.5ft). Let's say this is 10ft long and 10ft deep. Let's say the drop is 10ft long and starts at 3.5ft ending at 10ft. Say it's 3.5ft deep, it goes for the first 13ft of the pool, that's 18x13x3.5 is 819 cubic feet. How long does that portion go for x 18ft wide x depth. So the easy way to do this is split it into sections. First you want to find volume in cubic feet then you can easily convert that to gallons. You can actually do the math yourself for more accuracy than a calculator.

Round pool volume calculator