Are you looking for a breakthrough idea to make a waterfall in your backyard? Creating a good waterfall design and having the right equipment can save your time and money.

Nowadays, creative innovations of cleverly disguised power filters that eliminate dangerous ammonia as they push water from your pond to the top of the falls, or pre-formed rock designs that take the hard work out of building cascades and water course, adding a water feature to your pond has been easier than ever.

Here are a few tips to remember as you plan your project:
You'll need to decide on how big the waterfall will be and how to control the flow of the waterfall running downs. The consideration is the size of the pond pump needed to power the water feature of the pond. Pond pumps are rated by the gallons per hour (gph) or per minute (gpm) produced at various heights. You wouldn't want your waterfall to be too strong like Niagara Falls or too slow, and the filter will not work properly.
There are several factors to consider :-

1. Volume of the pond :-

A pond of 4 ft width, 9 ft length and 2 ft deep has a volume of (4x9x2x7.5) 540 gal.

2) Width of the flow of the water over the waterfall:-
The wider and deeper the waterfall is, the higher the required pump capacity. A waterfall of 15cm (6in) wide and 0.5cm (0.2in) deep will cycle 1300 ~ 1500 liters (285~330 gallons) per hour of water or 21.7~25 liters 4.75~5.5 gallons) per min.
   
3) Maximum recommended flow rate for the biological filter and UV unit:-
Rule of thumb says the recommended flow rate of the filter is at least half the volume of the pond per hour. For example, that a pond that holds 540 gallons should be powered at a minimum by a 270-gph pond pump.

From factors 1,2 and 3, a reasonable pump capacity would not be 270-gph because it's good enough for the filter and pond but it would not cope with the waterfall which requires 285~330-gph. The recommended pump capacity should be at least 285-gph.
 
Choosing your pump capacity which is over than the calculated flow rate will do no harm to your pond, on the other hand your pond will be cleaner faster, more than once in every 2 hours.
But if a waterfall or pond filter is to be powered with the pump, then the height and width of the waterfall and/or the flow rate of the pond filter have to be taken into consideration.

If a very high or powerful waterfall is desired, it is often more advantageous to power the pond filter and the waterfall with separate pumps. A pond pump powerful enough for a large waterfall may be too much for the pond filter (especially biological pond filters need slow water movement to be effective; about 10~20 minutes)