What size pump?

I have taken over a pond with a waterfall and when I checked the size of the pump I found that it was 690 watts which appears to me to rather expensive to run.
My wife would like a gentle trickle of water and I have no idea what size pump to go for.

 

Size of pump is determined by what it is to do, as in how many litres / minute does it have to move and to what height, without this information its not possible to suggest a particular pump.

I would also ask, is the waterfall the outlet from the biological filter?

 

At the moment the pump serves a one and a half inch diameter pipe pumping the water four foot high along a pipe which is about twelve feet in length. The problem is that one cannot borrow a pump of a chosen size to test it out so I don’t know where to go from here.
I have no idea what a biological filter is.

 

How about a picture?

A biological filter is if you will a miniature sewage treatment plant to keep pond water fit for fish to live in. They are often used in combination with a "UV" This keeps the water from going green.

How wide is the water fall, picture(s) would be really good.

 

Many thanks, I will give it a try tomorrow if everything is not frozen.

 

JWK's suggestion will tell how much water is required / min BUT when you look for a suitable pump you have to take into consideration head height and hose diameter, but that aside pictures would still be useful as I am wondering is there a biological filter, because you can get pumps for: fountains, water falls, biological filters and sumps they are all different and not "interchangeable"

 

Many thanks for all the advice. The pump serves a one and a half inch diameter pipe pumping the water four foot high along a pipe which is about twelve feet in length and it is directed into a hidden gutter running along the top of the waterfall with gaps for the water to exit. The waterfall is about six feet wide running down a gentle six foot length which drops into the pond one foot above it. The stinking Herons have taken the fish so I do not need a bilogical filter.

 

The reason it is a powerfull pump that you have, is although a smaller pump would lift the water high enough there would not be the VOLUME of water to reach the end of the hidden gutter, it would just dribble out of the first two exits
Needing a biological filter or not is not the point, If yours has one then any other pump would not suffice unless it was specific for a bio filter

Jack McH

 

1) Do you need water to circulate? e.g. because you have fish

2) Do you want to use the water fall only for "show"?

1 + 2 Get a second lower-flow pump and use it most-of-time time to circulate the water - without lifting it the 4' to the top of the waterfall.

2 only - only turn it on when you want a "show"

690 watts running 24/7/365 is about £1,000 a year in electricity :( at the very least get a timer so it doesn't run all the time - I run mine for 6 hours overnight on economy-7, and have an override switch when people are coming round and we want to hear the tinkle-tinkle of running water :thumb: or get a lower wattage pump that has the same Lift and Throughput (Pump will be more expensive than your current one, but it will save you more in electricity over its lifetime)

If you have some fancy Koi carp then you won't be able to get away with just running it for a few hours a day, but if you have a second pump you won't need to "lift" the water 4' with the big pump all the time.