EASY PLANNING FORMULAS AND CONVERSIONS

 

Here are a few simple formulas and conversions that may help you in planning your water garden and selecting proper equipment. Formulas are approximate figures only. Remember you cannot over filter so in hot climates, direct sun or shallow ponds oversize your filter when possible. 

HOW TO CALCULATE SIZE OF POND LINER

 

Length = (Depth x 2) + Length + 2 feet

 

Width = (Depth x 2) + Width + 2 feet

 

Example:  For a finished pond of 8' x 10' x 2.5', purchase a liner which measures at least

 

Length = (2.5 x 2) + 10 + 2 = 17'

 

Width = (2.5 x 2) + 8 + 2 = 15'

HOW TO CALCULATE GALLONS IN A POND

 

Length x Width x Depth x 7.5 = Pond Gallons

Example:  12' x 10' x 2' x 7.5 = 1800 Gallons

WATERFALL WEIR RATES

Width of Weir (GPH/GPM)   per linear foot

 

360/6

600/10

900/15

1680/28

2400/40

4500/75

6720/112

Thickness of Water

 

1/4"

3/8"

1/2"

3/4"

1"

1.5"

2"

PIPE / TUBING FLOW RATES

Max Flow (GPH/GPM)

 

300/5

720/12

1200/20

3000/50

4800/80

6000/100

9000/150

12000/200

Inside Diameter of Pipe / Tubing

 

1/2"

3/4"

1"

1.5"

2"

2.5"

3"

4"

HOW TO CALCULATE TOTAL DYNAMIC HEAD

 

TDH = Friction Loss from length of pipe (run) + Vertical Rise (distance from surface of water to top of water feature)

METRIC CONVERSIONS

 

1 Teaspoon = 5 ml

1 Tablespoon = 15 ml

1 US Gallon = 3.78 liters

 

ABBREVIATIONS

 

GPH = Gallons Per Hour

GPM = Gallons Per Minute