Filter Pumps

Filter Pumps are big and powerful pumps for sending dirty water up to a filter or a waterfall.  They usually have an outer casing strainer that allows quite large particles of waste through so they don't clog up like a smaller pump with a finer strainer would.  Beware just choosing the cheapest option as the cheaper ones often have a shorter guarantee (3 years instead of 5 years) and they have higher running costs, so what you save in purchase cost you loose in your electricity bill! 

Which size to choose?

There are two things to think about here:  the overall volume of your pond, and whether you need the water flow to look a particular way.  Simply, the more waste in your pond, the more circulation you need, so the bigger pump you need! 

Picking by pond size: The model number of each pump is usually the 'flow rate' or amount of water it can pump in 1 hour, so a pump called a 5000 would pump 5000 l/h.  In a pond with a few fish in, you should aim to circulate the whole volume of the pond once an hour, so that 5000 l/h pump would be perfect for a 5000 litre pond.  If you have lots of fish, or really greedy/chunky fish like koi, you need to double the circulation, so you'd choose a 10000 l/h pump.  If you didn't have any fish, you could get away with circulating ever 2 hours, so a 2500 l/h pump would do nicely.

Picking by waterfall size: If you want the water to cascade nicely down a waterfall once it's come out of your filter, you need to make sure your pump is strong enough to a) send the water all the way up hill (against gravity) to the top of your waterfall and b) that there is enough water flow for it to spread out nicely and tumble down like a proper waterfall.  If you choose a pump that's too small, you'll end up with a feeble trickle!  For a decent waterfall you need 1000 l/h for every 10cm of waterfall width.  So if you have a 30cm wide waterfall, you need to make sure your pump is doing at least 3000 l/h.  The higher you send the water above the surface of the pond, the slower the flow gets as it fights gravity, so always go up at least one size to make sure it still has the flow you want by the time it gets to the top!  Every pump comes with a 'performance curve chart' to take the guess-work out of this, so ask us if you want help choosing!