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Calculate pet medication dose from body weight and drug concentration. Convert mg/kg prescriptions to tablet or liquid volumes for dogs and cats.
Multiply length × width × average depth for volume. Use average depth if the pond bottom slopes — (shallow end + deep end) / 2.
Volume (ft³) = L × W × Avg depth; Gallons = ft³ × 7.48Use π × radius² × average depth. Measure radius as half the diameter at the water surface or average of top and bottom if walls slope.
Volume (ft³) = π × r² × Avg depth; Liters = m³ × 1000Divide irregular shapes into rectangles, triangles, and semicircles. Sum each section's volume. Alternatively use water meter fill method: volume = fill flow rate × fill time.
Total volume = Σ(Section volumes)Updated: July 2026
Volume = 10 × 6 × 3 = 180 ft³ × 7.48 = ~1346 gallons (~5095 liters). Size filter for 1346 gal turnover every 1–2 hours.
Radius 4 ft: π × 4² × 2 = ~100 ft³ = ~751 gallons. Suitable for a small goldfish collection with adequate filtration.
Pond 12×8 ft, 1.5 ft shallow end, 3.5 ft deep end. Average depth = (1.5 + 3.5)/2 = 2.5 ft. Volume = 12 × 8 × 2.5 = 240 ft³ ≈ 1795 gallons.
Average the shallow and deep end depths. A pond sloping from 1.5 to 3.5 ft has 2.5 ft average depth, not 3.5 ft — overestimating volume by 40%.
Subtract 10–15% for rock, gravel, and plant displacement. Medication dosing on overstated volume underdoses; filter undersizing on overstated volume under-filters actual water.
Pond volume determines filtration capacity, pump flow rate, UV sterilizer sizing, medication dosing, and safe fish stocking levels. This calculator computes water volume for common pond shapes — rectangular, circular, and irregular — in gallons and liters.