Mag Drive Pond Pump Information
One of the best pump for pond out there you can buy is a mag drive pond pump. Magnetic-driven pond pumps use less energy and have a longer life than a direct drive pond pump would. The pumps work in short using a magnet that is attached a motors shaft in a sealed pump chamber.
Then, another magnet which is connected to the pump impeller in a different chamber spins. As the first magnet on the motors shaft spins when the power is turned on. So, instead of a electrical morot you actually have the magnets in the pumps motor that actually spis the impeller.
The drawback of mag drives is that they are a bit more expensive. Not as expensive as a external pond pump, but more expensive than direct driven.
The benefits of mag drive pond pumps in my opinion make up for the added cost up front. But like all kinds and brands of pond pump it depends on your application. You should still buy the best quality pump you can afford either way.
The least expensive pond pumps have a relatively short life span. Which may work on very small water features, but they tend to clog up easy and burn out.
Most moderatly priced pumps will be made with aluminum or cast iron housings. Also will have a corrosion resistant epoxy finish on the outside to prevent rust. They are more durable and impact resistant than plastic pond pumps and come in a range of capacities. One thing you have to take keep in mind though.. with aluminum housing it make corrode with water frequently treated with pond chemicals.
High quality pond pumps are the longest lasting (but most expensive.. you get what you pay for) and are usually made out of brass, bronze, and commonly stainless steel. They can stand up to chlorine, salt water, and pond chemicals and handle continuous operation which is important for a pond ecosystem. If you expect a pond to be a permanent feature in your landscape a high quality mag drive pond pump is well worth the extra cost.