Basic Pond/System Design
There are some basic rules that you must apply when building any pond. It all starts with the total volume of water the pond holds. This is because the number one goal is to have a once an hour turnover rate. What this means is that if you have a 1000 gallon pond, you want to pump at least 1000 gallons an hour through your filtration and therefore have at least a 1000 gallon per hour pump. If you had a 3000 gallon pond you want to pump at least 3000 gallons an hour through your filtration and thus a 3000 gallon per hours pump, so on and so forth. So as you can see the volume of the pond dictates at minimum the size pump you should have. I say minimum because this does not take into account things like head loss, friction loss, etc. that will cause you to lose some of that flow.
For larger ponds from 8000 gallon volumes and up it is acceptable to have a slower turnover rate of once every two hours. The only time I do this, however, is when the customer can’t afford the larger equipment associated with these larger flow rates and pumps. A once per hour is the best, but once every two hours can work.
Now with this known flow rate and pump you now must have properly sized plumbing pipe to accommodate that flow rate safely. The bigger the pipe the more flow it can handle. There are plenty of charts available online to help you choose the proper size piping for your pond plumbing. This is important because if you have too small a diameter of piping and try to pump more water through it than it can safely handle, you will cause extreme and possibly unsafe pressure to build up. This could lead to failure of your plumbing fittings, joints, or the pipe itself. So match your pipe size to your pump flow rate using the available charts online.
With all of the above in mind you must also account for the fact that you may want your waterfall to look like Niagra Falls! In that case you may need even a larger pump to get the aesthetic look you want. It is fine that your turnover is more than once per hour, but I would not want anything less than a turnover rate of once per half hour. Anything faster will impede your filtration from working properly possibly. So in this case you still need to match the piping and all associated filtration equipment to the flow rate of the pump. As for filtration equipment, these include things like waterfall filters, skimmers, UV lights etc a from pump to anything that the pumps sends water through for everything to work properly.
Once you have all of this in place you will be well on your way to having a functional design. There is much more to it, however, that is discussed in other sections of this site under pond design. For now this is enough info for you to be able to comprehend the remaining info in this article on why you have filtration, and what is really going on in the water.
So now that we have helped you so, be gracious and buy your pump from us.