18 × 36 ft pool volume
An 18 × 36 ft pool holds
26,700gal 101,000LAt an average water depth of 66 in.
Gallons at every fill
| Average depth | Holds |
|---|---|
| 48 in this page |
19,400 gal 73,400 L |
| 54 in this page |
21,800 gal 82,500 L |
| 60 in this page |
24,200 gal 91,600 L |
| 66 in this page |
26,700 gal 101,000 L |
What to add
| Fixes | Product | Add |
|---|---|---|
| Lower pH −0.5 pH |
HASA Dry Acid | 3.34 lb |
| Raise total alkalinity +40 ppm |
HASA Alkalinity Up | 14.94 lb |
| Raise pH +0.3 pH |
HASA Soda Ash | 8.01 lb |
| Raise free chlorine +2.5 ppm |
HASA CHLOR | 2.13 qt |
| Shock the pool +9.5 ppm |
HASA CHLOR | 8.10 qt |
Not quite your pool?
Change any measurement and every figure on this page is worked again: the gallons, the drawing, the fill table and each dose.
Pools near this one
- 23,700 gal How many gallons a 16 × 36 ft pool holds
- 21,100 gal 16 × 32 ft
- 32,900 gal 20 × 40 ft pool, in gallons
- 16,100 gal 14 × 28 ft pool, in gallons
- 8,230 gal 10 × 20 ft
Updated October 2026
Sources and dates
Ranges are quoted from the code named beside them, product strengths from the manufacturer's own product page, each retrieved on the date shown.
- COMAR 10.17.01.45 A(1) · https://www.law.cornell.edu/regulations/maryland/COMAR-10-17-01-45 · 2026-09-17
- HASA · https://hasa.com/pool-chemical-calculator · 2026-09-17
- COMAR 10.17.01.45 A(2) · https://www.law.cornell.edu/regulations/maryland/COMAR-10-17-01-45 · 2026-09-17
- Florida 64E-9.004 (1)(d)2 · http://flrules.elaws.us/fac/64e-9.004 · 2026-09-17
- HASA Dry Acid · https://hasa.com/product/dry-acid · 2026-09-17
- HASA Alkalinity Up · https://hasa.com/product/alkalinity-up · 2026-09-17
- HASA Soda Ash · https://hasa.com/product/soda-ash · 2026-09-17
- HASA CHLOR · https://hasa.com/product/hasachlor · 2026-09-17
This site publishes calculated water volumes and chemical quantities for home pool and spa owners. It is not a health, safety or professional service, and it does not replace the instructions printed on the product you are holding. Not affiliated with, endorsed by or sponsored by HASA, Pyrock Chemical, Pentair, Hayward, Sonoma Hot Tubs, the Centers for Disease Control and Prevention, or any state health department. Product names are the trademarks of their owners and appear here only to identify the strength of what is in the container.