New study on propeller pumps has some interesting findings! EcoTech vs Tunze?

[dawgface]

Some of you may have read the article that was released today over at Advanced Aquarist that shows the output flow of propeller pumps and compares them.

Couple things to note is that the EcoTech Vortech rated better that the manufacturer claim and the Tunze Pumps rated lower.

Check it out and let's discuss it here in this thread.
http://www.advancedaquarist.com/2011/7/aafeature">http://www.advancedaquarist.com/2011/7/aafeature</a>


Here are the tested pumps and their advertised flow ratings as well as what the rate actual was.



Info from: [IMG]http://www.advancedaquarist.com/2011/7/aafeature"><span style="color: #003366;">Advanced Aquarist</span></a>
PUMP-----------------------Advertised Flow-------------Actual Flow
Aqueon 2400--------------------2400------------------------2744
Coralife CP 2900----------------2900------------------------2437.2
Ecotech Marine MP-10----------1575------------------------2460.3
Ecotech Marine MP-40----------3200------------------------3781.2
Ecotech Marine MP-60----------7500------------------------8509.8
Hydor Koralia 5------------------1650------------------------2597.59
Hydor Koralia 6------------------2200------------------------2205.6
Hydor Koralia 7------------------2700------------------------2659.1
Hydor Koralia 8------------------3250------------------------3188.3
Maxijet 1200----------------------295-------------------------405.7
Tunze 6105----------------------3434------------------------2358.2
Tunze 6205----------------------5811------------------------3234
Tunze 6305----------------------7925------------------------3597.3

[IMG]http://i6.photobucket.com/albums/y232/revhtree/data.jpg alt="" />

<span style="font-size: 11px;">This thread was taken from another forums site. I wanted to bring it here for discussion. </span></em>

Edit: Response from Tunze regarding their performance.

Where did we get our flow numbers?

We derived our flow numbers in two ways, by a test termed a “bag test” and by theoretical calculations. The bag test is just as simple as it sounds, a collapsed bag is placed over the end of the pump and inflated by the pump with water, the time to fill the bag is measured and the flow is calculated. This method has definite limitations, it places backpressure on the pump, and it cannot be used on larger pumps given the limits of bag volume and reliable timing. For all pumps a theoretical calculation is made based on propeller surface area and rotation frequency.

Our bag test results are consistent (within + or – 10&#37http://www.reef2reef.com/forums/images/smilies/icon_wink.gif" alt="" /> with theoretical results on the pump models 6015, 6025, 6045, 6055, 6065 and 6085. This led us to rely on theoretical numbers. The biggest pump that a bag test can be performed on is the 6105 and the inaccuracy of flow numbers on the 6105 has a different origin than 6205 and 6305 inaccuracies. The 6205 and 6305 flow numbers were only based on theoretical calculations. The 6105, when released, was near specified flow and was bag tested with a result of 90% of theoretical, however, later modifications to reduce noise relied on theoretical flow numbers and flow was lost to these modifications. On models 6205 and 6305 the fundamental issue is that the theoretical flow cannot be reached due to overly constricted intake and output.
Going Forward

Over the next 6 months we will perform numerous tests aimed at improving our pumps. We believe pump volume alone does not equal effective flow, the ability to direct that flow is also important. In much the same way as the light available from a bulb means little if it cannot be properly directed into the aquarium, the flow rate at a pump is not as important if there is not sufficient flow at the corals.. We have since purchased two flow meters, one uses comparable sonic technology and the other uses a propeller akin to a common wind gauge and while we have found that using the comparable meter and methodology our results are the same. We have also found the propeller based meter gives divergent data, this data indicates that our more forceful targeted flow draws in current as the distance from the pump increases and that our total flow produced may be well higher than the flow of the pump itself. Use of a different methodology may very well give the opposite results, but this does not dispute the results of this study, it will only show that flow is complex and has numerous aspects which we are only beginning to understand. At this point we conclude that the study is correct for the flow produced by the actual pump itself and we will improve the pumps in a retrofittable manner, though this will take time as new parts must be designed and produced. Improvements will be based on increasing intake surface and reducing output restrictions on models 6205 and 6305 and increasing rotational speed for 6105. We would like to thank Sanjay Joshi, Bill Straka and Michael Sandford for performing this study, graciously informing us of the results and giving input on proposed solutions. We believe it is a step forward in uncovering many of the mysteries of high volume, low pressure flow which until recently was nearly impossible to quantify. [/QUOTE]

 

[mvm]

Tunze's response basically says, "We know our calculations are wrong, but we have directional flow!!!" Pretty funny.

 

[dawgface]

Their testing consisted of a bag of which they could only test one pump in which the rest needed to be calculated by theoretics!! LOL

Based on this I can only assume their "theoretics" were calculated by a 3rd grader.

 

[mvm]

The directional flow was a shot at vortech, BTW.

 

[smallblock]

I was impressed by the aqueon's output as well, I was considering them untill I got a great deal on the vortech. I like the aqueons, the whole tunze thing is very dissapointing I've never really liked them anyway but I've never owned them either. I dunno I hope they make it right and am glad that they confessed to making a mistake. That's the way bidness is supposed to be done. I really hope they make it right for their loyal customers.

Edit: I wish they would have tested an upgraded mj with the conversion kits, I'm actually impressed by what they put out too.

 

[ralph atl]

yes, quite interesting....Vortech's are king....

 

[sharkbait]

Good thing I have always used Vortechs. In the past I have almost pulled the trigger on some Tunze's. I wonder how this will impact all of the current used Tunze's on the market right now? I have seen a couple of sets floating around...

 

[acroholic]

Nothing like almost 25,000 gallons an hour moving around your tank with 2x MP60 and 2x MP40s.

 

[lifestudent]

Acroholic;666217 wrote: Nothing like almost 25,000 gallons an hour moving around your tank with 2x MP60 and 2x MP40s.

On what size tank?

 

[acroholic]

A 300 gallon Marineland DD. That is based on the above results. The Official EcoTech rating for the MP60 is 7500 gallons an hour and 3400 for the 40, so officially it would be 21,800 an hour for all 4.

 

[grouper therapy]

mysterybox;666196 wrote: yes, quite interesting....Vortech's are king....

And just think they did not even measure the amazing "undertow" from the vortech that kicks up the sandbed. Maybe they just pointed it up at a slight angle? :lol2:

 

[grouper therapy]

I can't believe that no one mentioned the performance of the koralia's
The Koralia 5 had the highest percentage of change in performance above the advertised gph
The Koralia 7 had the highest gph per watt of any of them.
Based on that DATA koralia would be king

 

[hnguyen]

Anyone get an E-mail from Echotech today talking about this test as well? I just got an e-mail about it.

JULY 14, 2011
EcoTech Marine Pumps Deliver More Flow than Promised
New study proves that the flow from the VorTech family of pumps exceeds even the company's own advertised claims
EcoTech Marine, the company that revolutionized the reef aquarium propeller pump, is pleased to announce the results of a scientific study on flow rates published in this month's edition of Advanced Aquarist.
Dr. Sanjay Joshi, Ph.D., professor of Industrial and Manufacturing at the Pennsylvania State University, conducted the study. He used a proven method to most accurately determine the output flows of several leading aquarium propeller pumps. The study scientifically shows the entire VorTech line delivers superior flow rates far in excess of what EcoTech Marine itself was claiming in its own marketing and advertising.
The MP40, the VorTech that started it all, delivers 18.2% more than its advertised claim of 3200 GPH&#8212;netting 3781 GPH in the study.
The MP10, ideally situated for tanks smaller than 50 gallons, has an advertised flow rate of 1575 gallons per hour (GPH). The study showed a GPH of 2460&#8212;a 56.2% increase over the advertised amount.
The MP60, ideally suited for larger tanks, has an advertised rate of 7500 GPH. It delivered 8509 GPH in the controlled study&#8212;an increase of 13.5%.
"At EcoTech Marine, we pride ourselves on delivering technologically superior products with exceptional value," said Tim Marks, president of EcoTech Marine. "Using the most accurate equipment and technology possible to measure water flow, Dr. Joshi looked at a wide range of pumps from a variety of manufacturers. The fact the VorTech delivered superior results is a testament to our unrelenting commitment to engineering and manufacturing the most advanced products in the industry."
In an effort to standardize the flow measurements and claims for powerhead manufacturers, EcoTech enlisted the help of Dr. Sanjay Joshi to design a study utilizing the latest in analytical techniques available. To perform the study, Dr. Joshi used a Sontek 10-MHz Acoustic Doppler Velocimeter in a 350-gallon aquarium. The velocity profile of the pump exit flow was measured at a distance of one diameter downstream from the output of the pumps, and this measurement was used to determine the volume flow rate output.
"We're very pleased with the results of the study," said Marks. "The loyalty of EcoTech Marine customers has been rewarded. Reef aquarists purchase a pump for an expected performance, the most important of which is flow rate. We'd rather under-promise and over-deliver any day of the week to earn our customer&#8217;s loyalty."
Click here to read the full article and see how VorTech stacked up to the competition.