PUMPS IN GENERAL
If you plan to move water in your pond you will need a pump. This goes for fountains, waterfalls, streams or ornaments.
Be sure you have a GFCI or ground fault circuit interrupter installed or available to connect the pump to. Water and electricity DO NOT MIX!
Pumps are available in both submersible and external. The smaller pumps are the most economical in submersible models, while larger pumps are more economically run in external models.
These type pumps are placed directly into the water. The units are sealed and need as a water source to run. NOTE: Do not run a submersible pump dry. You may be buying another one!
The nice thing about these pumps is that there is no noise to distract you from the sound of your water feature.
A recent introduction is the magnetic drive pumps that do not contain oil coolant and are energy efficient. They generally cost about half to run but cost a little more than oil filled.
When we are talking external, you are probably thinking…oh a swimming pool pump!
Some pond keepers still use this type of pump, however, most opt out because of the daily and weekly maintenance involved. Most people want to spend their time enjoying the pond not working on it!
Sand filtration types quickly clog up from the debris that is associated with all ponds. Once again you will spend a lot of time cleaning. Of course, if time is not a problem, they do work.
You can also adapt this type of pump and use larger media such as gravel, but it is heavy and hard to clean.
Special external or centrifugal pumps made especially for ponds are available. One good point to make is that you can access them outside of the water.
Remember that some of them are noisy, so you will have to decide if that is a major factor.
All in all, we opt for the submersible 9 times out of 10 and so do our customers
You have 2 real choices when it comes to piping your water from the pump to your water feature. You may use flexible tubing or plastic PVC piping. Rigid PVC is less expensive but you must glue every joint and piece together and there is always a possibility of leakage outside the pond. If you use this type be sure it is the white PVC which is suitable to run potable water and is safe for the fish.
Flexible tubing is the most common and is available in a range of sizes depending on the application. Here is a chart that might help.
The cleanliness of your water will determine how much attention you will have to pay for your pump.
Water that contains soil, organic matter, and algae while cause deposits to form on the intake port. The collected matter will stress out the pump, so be sure you keep the debris from building up.
Your first indicator will be the water flow. When matter impacts the intake port the water flow decreases. You will notice that your waterfall slows or that your fountain is not working properly. This would be a good time to shut it down and clean it.
Another idea would be to fill up a bucket half full with lava rock, place the pump inside the bucket and continue filling the bucket until it is 3/4 full. This helps to filter out the large particles that clog the intake and may require you to clean it only once or twice a season. Of course, this would depend on many factors.
Either way, you go, choose a pump that meets your needs.
A good rule of thumb is to be sure the pump will recycle the entire pond every hour. That way you increase the oxygen level for the fish while filtering as much water as often as possible.