Choosing A Pond Pump

Pond pumps are the very heart of any fish pond. All water gardens can be enhanced by the addition of water fountains, waterfalls, and other moving-water features.

The pond pump is your best friend if you're planning to create water effects in your pond. Even if you are not planning to have fountains, or waterfalls, pond pumps are essential for oxygenating your pond.

When choosing a pond pump, keep the following requirements in mind. The first thing is to determine your required flow rate. Your minimum flow rate should be at least half of your pond volume. So, if you have a pond with 2,000 gallons of water then your pump needs to at least circulate 1,000 gallons per hour (GPH). This is a minimum. You might find that 1,000 GPH is not enough if you will be including, for example, a waterfall that is more than 10 inches wide. Generally a waterfall requires 100 - 150 gph per inch of width of the weir (the portion that the water spills over). This can vary depending up on how smooth or rough the weir is. You will also need to be sure that the pump moves enough water to satisfy the requirements of your filter and ultraviolet sterilizer.

So, which type of pond pump is right for you? That depends upon your pond's design and purpose. Submersible pumps are best suited to small to medium sized ponds with roughly 200 - 800 gallons of water. These types connect easily to most of the submersible filters built for small to medium sized ponds. Flow rates usually range between 250 GPH and 4,100 GPH. for a larger waterfall pump.

Submersible pumps operate inside the pond. They are generally low cost to buy. Many models of submersible pumps are available, and they are a good choice for flow rates around 1,000 gph or less. Submersible pumps are usually less expensive and easier to install than an external pond pump. On the downside, they can cost more to operate and usually don't last as long as external pumps (having shorter manufacturer warranties.) The motors of most submersible pumps are totally encased in a resin so that they are safe to use underwater. Most submersible pumps cannot be repaired, for safety reasons. So, once it wears out, it's time to get a new one!

Many variables are taken into account when determining how long a good submersible pump will last.  Issues such as how dirty the water is, how often the pump is cleaned, and if it is operated nonstop, all will influence the life span of a pump.

Submersible pump power supplies come in 110 – 240 volts, 12 or 24 volts, or solar powered. Solar submersible pumps are becoming more popular - but you need lots of sun for effectiveness and, of course, they won't run at night when your water needs the most oxygenation.

There are several advantages to a submersible pond pump over a submerged pump. They are more energy efficient, resulting in lower annual operating costs and they tend to last longer. On average, submersible pumps tend to wear out after about 1 year because they spend their life sitting smack in the middle of pond sludge which eventually damages the pump's impeller.

Overall, an external pump has a longer mean time between failure (MTBF) than it's submersible cousin. Most submersible pumps carry a 1 year warranty, and tend to last up to 18 months.  Do the match and you'll see that a longer-lasting external pump is almost always the best bargain.

Finally, unlike a submersible pump, most parts on an external pump can be replaced rather easily. As I mentioned before, when something goes awry with a submersible pump, it's next home is the trash can!