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Efficiency & Price Assessments By Steven Pro
Powerheads and propeller pumps are very common devices for providing circulation in marine aquarium systems. And, while many folks evaluate their needs and the pumps they are looking at by the gallon per hour rating, a conscientious consumer will go a step further. Gallons per hour is a fine starting point, but just as important in making this purchasing decision is how many watts a unit uses and what the price of the unit is. These additional factors go a long way in determining how efficient a given pump is. I looked at and compared a number of brands and models. I did not, however, endeavor to include every given manufacturer and model. I restricted my search to brands that I felt comfortable in using and with a strong record of performance and reliability. I also confined the search to pumps that I have used. There are some well-known brands that I left out because I could not recommend them in good conscience. However, feel free to use my template to judge any brand and model that you desire to see how they might stack up in this comparison. There are also some brands that I may simply not be aware of. I have been around for a while and am relatively familiar with what is available, but there are always new brands entering the market and there are some regional variations. Certain manufacturers have better distribution channels in certain areas of the country. So, just because a particular pump may not be on this list does not mean I would not necessarily use it. It could be that I simply am not familiar enough with the product line to judge them. It is also important to note that not all of these pumps are designed the same way or for the same function. Hagen, Maxi-Jet, Rio Seio and Tunze pumps are for sumberged, in tank use only, Iwaki pumps are for external use only and Eheim and Supreme Mag-Drive pumps can be used either way. Most conventional pumps use a rotating impeller to move water at a relatively high pressure through a relatively small opening. Tunze stream and Rio Seio pumps use propellers and turbine type mechanisms to move water at a relatively low pressure through a relatively large opening. The table below shows the flow, power consumption and price of several popular pumps. Also shown are efficiency (GPH/Watt) and cost effectiveness (GPH/$).
If you take a look at the efficiency rating, that of gallons per hour per watt used, you will quickly notice that the Tunze brand propeller pumps absolutely blow the competition away. They produce over 130 gallons per hour per watt consumed while most other typical impeller style pumps produce around 20 gallons per hour per watt used or less.
The common complaint with the Tunze Stream pumps is their comparatively high initial purchase price. But, as you can also see from the chart illustrating the gallons per hour produced per dollar for the Tunze’s, you will see that they are right in line with other pumps. So, based on this comparison, the Tunze Stream pumps are a good value based upon their gallons per hour per purchase price and they will save you money long-term because of their extremely low wattage consumption per gallon per hour produced. Head to head comparison of new generation high efficiency flow pumps In this section, I will compare the Rio Seio pumps head to head with the Tunze Streams. The high flow rate and attractive purchase price has fueled the popularity of the seios. Unfortunately I, along with others have experienced a significant number of malfunctions with RIO products, causing me to hesitate to use them in my own or my customers tanks. Proponents of the Seios point out that the problems with Rio products were with a different line of pumps and that the Seios have been reasonably trouble free. There have been numerous reports of Seios not restarting after being turned off or in the event of a power outage, but this is a relatively minor inconvenience and is outweighed by their flow rate and price.
As you can see from the charts, the Tunze Stream pump line is on average two and a half times more efficient (gallons per hour per watt consumed) than the Rio Seio pump line. But, the Rio Seio pump line is on average one and a half times less expensive than the Tunzes based on their gallons per hour per initial purchase price figures. However, that is not the complete story. A pump costs an aquarist more than just the initial purchase price. The cost of operating it in terms of electrical consumption also needs to be evaluated. As an example, I will compare the Tunze Stream 6060 and the Rio Seio 1500 (1,600 and 1,500 gph respectively). If both pumps are run 24 hours a day at $0.0669/kW-hour (courtesy of Duquesne Light Company), it would take 4.25 years to recoup the difference in the initial purchase price. In my area, we pay comparatively little for electricity. Other areas of the continental United States pay up to $0.14/kW-hour http://www.eia.doe.gov/cneaf/electricity/epm/table5_6_a.html. At that higher electrical rate, one would recoup the price difference for the same two pumps in just over two year’s time. Interested readers should calculate this pay off time for themselves based on their local electric rates.. In my opinion, the time to make up the price difference matters little. I am in this for the long haul. I have been keeping marine aquariums for over a decade now and don’t foresee stopping anytime soon. The biggest difference for me is in the reliability I have experienced with both companies’ products. I own a Tunze 3115 protein skimmer that is approximately ten year old and works as well today as when it was brand new. I have sold a number of them to maintenance customers over the years that operate trouble-free, as well. In contrast, my experience with Rio has been less than stellar. As such, Tunze get my nod and my money. One final note: While it may seem to some that I am absolutely enamored with Tunze Streams, they do have one drawback. You need an advanced degree in mechanical engineering to properly assemble the mounting brackets! They are needlessly complicated, but this is a relatively minor trouble compared to their overall pluses. <Editor's note: As a big fan of Tunze Streams, I categorically agree with Steve's findings. The only other caveat with these pumps is that you must follow a regular maintenance schedule, or they will quit functioning, with their on-board alarms going off at very annoying moments, like 3:30AM on a Monday morning! S.F.>
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