June 1, 2008 Chemical engineers developed a pump that splits into two pieces, a propeller for the interior of the aquarium and a motor for the exterior, connected across the glass wall by strong magnets. The magnet is made of neodymium, a strongly magnetic rare earth metal. The motor transmits torque through the magnet to the propeller inside the tanks, circulating water inside the aquarium.
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Maintaining a saltwater aquarium can be an expensive hobby. Just setting up a 55 gallon tank can cost about $1500s -- and that's without fish! But a group of young engineers are using a rare earth magnet to build a better environment for ocean life and help precious species thrive in captivity.
To keep your aquarium a healthy place for fish and other salt water creatures live, you need to know the science behind a thriving set up. Coral needs an ocean-like environment in order to survive.
"As you can imagine on a coral reef, there's wave action," Greg Appleton, a tropical fish importer, told Ivanhoe. "Water flows back and forth and back and forth and this is very important as it draws nutrients to the corals and removes wastes away from the corals."
Aquarium enthusiasts use a series of pumps to create the undulating sensation of waves, but traditional pumps can cause a bad side effect. "These pumps create heat and these corals are very sensitive to water temperature," Appleton explained.
That's where mechanical and environmental engineer Tim Marks and his partners are making a difference. They've created a new pump that is literally split in half. "The pump is revolutionary in the sense that it takes the motor outside of the aquarium," Pat Clasen, cofounder of EcoTech Marine, told Ivanhoe. "It couples the propeller on the inside with the motor on the outside and they clamp together using magnets."
The magnets are made of neodymium, the strongest rare "Earth" magnet readily available. The magnets hold the two sides together through glass up to three-quarters of an inch thick. "Actually, all of our pumps wirelessly communicate," Clasen says. "It's kind of like Bluetooth. So they can hear what the other pumps are doing and synchronize their efforts."
And with the motor on the outside, the heat dissipates into the air, not over the delicate reef, keeping your aquarium a healthy home to everything that lives in it! Ecotech says the "vortech" pump, as they've named it, is catching on. They've formed a company to market the product and are generating about $200,000 a month in sales.
WHAT MAKES MATERIALS MAGNETIC? Magnetism comes from the constant movement of charged electrons in atoms. As electrons swirl around an atom, they create an electrical current, and whenever electricity moves in a current, a magnetic field is created. So magnetism is a force between electric currents: two currents flowing in the same direction attract, while those pulling in opposite directions repel. The reason some materials are magnetic, while others are not, has to do with how the electrons are ordered.
A magnet is an object made of magnetic materials; naturally occurring magnets are known as lodestones. Every magnet has at least one north pole and one south pole. In fact, if you take a bar magnet and break it into two pieces, each of the smaller pieces will still have a north and south pole. The Earth itself is a giant magnet with a north and south pole, which is why a magnetic compass's needle always points north/south.
WHAT ARE THE RARE EARTH ELEMENTS? The rare earth elements are a class of 17 chemical elements, grouped together because of their chemically similar properties. They are usually soft, malleable and react easily with other chemicals, especially at higher temperatures. Despite their name, the rare earth elements are not especially rare. They can be difficult to harvest, since they are contained in other naturally occurring minerals as trace elements, and must be separated out.
They are used for many purposes, for polishing glass and optical lenses; as additives to strengthen soft metals; in permanent magnets; and as ceramics and as dyes for glazes and coatings. The phosphors, which glow when struck by light or an electrical charge, are used in. Rare earths can also be found in color televisions, fluorescent lighting, nuclear detectors, lasers, electronic components, jewelry, and as anti-corrosive additives in paints.
The Institute of Electrical and Electronics Engineers, Inc., the Materials Research Society, and the American Physical Society contributed to the information contained in the video portion of this report.

