Liner
Pool, pond, and aquarium calculators
Gallons in the pool, pounds of salt to close a ppm gap, and the weight of a full aquarium on its stand.
Pool Volume Calculator
Pool volume calculator for a rectangle, round, oval, or kidney pool, with a sloped-floor average depth. Gallons, cubic feet, and litres.
Pool Salt Calculator
Pool salt calculator. Pounds and bags to move from the current ppm to a target. The product label and the chlorinator manual win.
Aquarium Calculator
Aquarium calculator for a rectangle, cylinder, hexagon, or bow-front tank. Gallons and the weight of the water on the stand.
How these calculators work
Pool volume is the water shape. A rectangle is length times width times average depth. A round pool is the circle. An oval is an ellipse. A kidney or freeform pool is the bounding rectangle times a factor that starts at 0.85, and you can change it. A sloped floor uses the average of the shallow end and the deep end. One cubic foot is 7.48052 US gallons.
Salt is gallons times the ppm you still need times 8.34 pounds per gallon, divided by one million. Bags round up. The product label and the chlorinator manual take precedence, and this page does not tell you how to mix chemicals. Add salt in stages and retest. The aquarium calculator is the same volume idea in inches, including a regular hexagon and a bow-front approximation, then the weight of fresh or salt water on the stand.