Every cubic meter of pond water weighs one metric ton - and a 4 m round pond holds 6.3 of them. Enter shape, dimensions and depth to get volume, EPDM liner size, plant count and fish capacity.
How much water does a 2 meter round pond hold?
Every cubic meter of pond water weighs one metric ton - and a 4 m round pond holds 6.3 of them. Enter shape, dimensions and depth to get volume, EPDM liner size, plant count and fish capacity.
A round pond with a 2 meter diameter and a recommended depth of 1.2 m for fish holds a specific volume of water measured in thousands of liters. The EPDM liner needs to be larger than the pond itself - the formula adds twice the depth plus one meter of overlap on each side. Enter your exact dimensions below to see volume, liner size, plant count and fish capacity.
Parameters
Enter data for calculations
💡 Fill in all required fields to unlock the calculate button
Every cubic meter of pond water weighs one metric ton - here is what that means for your garden
A modest 4 m round pond at 1.2 m depth holds 15,080 liters of water - that is 15 metric tons sitting in your garden. The EPDM liner to hold it measures 7.4 m x 7.4 m and costs around $383 at $7/m2. The calculator works out surface area, volume, liner dimensions, how many plants you need, and how many fish the pond can safely support.
Four numbers that define your pond
12.6 m2
Surface area (4 m round)
15,080 L
Water volume (1.2 m deep)
7.4 x 7.4 m
EPDM liner needed
75 fish
Max capacity (5/m3)
How to use the garden pond calculator - step by step
- Pond shape - round is simplest to build and calculate. Kidney-shaped looks most natural. Rectangular suits formal gardens.
- Length or diameter - the main dimension. A 3-4 m pond is a good starting point for most gardens.
- Width - only for rectangular and kidney shapes. Leave empty and the calculator defaults to 70% (rectangular) or 60% (kidney) of length.
- Depth - 0.5 m for a water feature, 0.8 m for plants, 1.0-1.5 m for fish. Fish need at least 1 m to survive winter.
- Fish? - if yes, the calculator shows maximum stocking density (5 fish per m3) and warns if depth is too shallow.
- Liner price - enter your local EPDM price per m2 to see total liner cost. US average: $5-10/m2.
Pond volume and liner size by dimensions
| Pond (round) | Surface (m2) | Volume at 1 m | Volume at 1.2 m | Liner size (1.2 m) | Max fish |
|---|---|---|---|---|---|
| 2 m diameter | 3.1 | 3,140 L | 3,770 L | 5.4 x 5.4 m | 18 |
| 3 m diameter | 7.1 | 7,070 L | 8,480 L | 6.4 x 6.4 m | 42 |
| 4 m diameter | 12.6 | 12,570 L | 15,080 L | 7.4 x 7.4 m | 75 |
| 5 m diameter | 19.6 | 19,630 L | 23,560 L | 8.4 x 8.4 m | 117 |
| 6 m diameter | 28.3 | 28,270 L | 33,930 L | 9.4 x 9.4 m | 169 |
Fish capacity at 5 fish per m3 (1.2 m depth). Liner = diameter + 2x depth + 1 m overlap.
Did you know?
Practical examples
EPDM vs PVC liner comparison
| Feature | EPDM (rubber) | PVC |
|---|---|---|
| Lifespan | 30-50 years | 10-15 years |
| Price per m2 | $5-10 | $2-5 |
| UV resistance | Excellent | Degrades after 10 yrs |
| Flexibility | Very flexible, even in cold | Stiffens in cold weather |
| Fish safe | Yes (non-toxic) | Yes (if fish-grade) |
| 30-year cost (50 m2) | $350 (1 liner) | $350-500 (2-3 liners) |
FAQ
Related tools
Lawn Mowing Calculator
Calculate mowing time, fuel and season cost for your lawn - See calculator
Water Usage Calculator
Calculate household water consumption and costs per month - See calculator
Rainwater Harvesting Calculator
Calculate how much free water your roof collects per year - See calculator
Garden Irrigation Calculator
Plan drip or sprinkler irrigation for your garden beds and lawn - See calculator
Compost Calculator
Size your compost bin by household and garden area - See calculator
Calculator verified by the LiczGrupa.pl team
Content, formulas and results have been reviewed for accuracy and relevance by our team of specialists.

Reviewed by: Natalia Skrzek