I want to increase flow to my waterfall from 1,500 gph (gallon per hour) to almost 4,000 gph, what size pipe should I use?
To increase water flow to 4,000 gph you need to use the appropriate size of pipe. When using a 4,000 gph pump, a proper size of pipe would be two inch. A way to think about pipe size is to imagine drinking through a straw. A cocktail straw it would take longer than if you were to drink water from a standard size straw. • Up to 500 GPH: Use 1/2″ inside diameter • Up to 900 GPH: Use 3/4″ • Up to 1,500 GPH: Use 1″ • Up to 2,700 GPH: Use 1-1/4″ • Up to 3,600 GPH: Use 1-1/2″ • Up to 5,400 GPH: Use 2″ • Up to 13,500 GPH: Use 3″ • Up to 21,000 GPH: Use 4″ • Up to 42,000 GPH: Use 6″ A Tip: Avoid sharp 90 degree turns because it will reduce water flow. Consider using a plumbing connection called a sweep corner if you must. A sweep still has resistance but it has a bend and not a right angle.
