Tunze is being investigated by a law firm out of D.C.

[macawmagic]

I agree that measuring flow may be a complicated procedure, however i do feel that if the other brands who we all know are not known for there superb quality like that of tunze can get their numbers correct they why can't tunze? Does tunze not have access to the same level of engineering that koralia or maxi-jet have? I dont think anyone here is refuting the quality and customer support received with a tunze product, the problem lies in that there advertised numbers according to the test conducted are very very inaccurate.

What i find comical is that this test shows that a MP-10 produces 56% more flow then advertised and tunze 6305 produces 54% less that advertised. The 6305 is $744 according to marine depot and produces results that equal the Vortech MP-40 that cost $300 less. I wonder does the 6305 come with a controller that offers the type of settings that an MP-40ES does?

If you put a tunze 6305 and a vortech mp40 in the same tank and test them side by side...guaranteed you will see how much more flow the tunze does than the vortech...I don't think many people have used both products, and only if you have do you realize how different the flow patterns are. If you look at the test tunze did right after you can see the difference. The vortech produces a turbulent pattern while the tunze produces a linear pattern. Who says that the same exact test can accurately be used to measure both types of flow? GUARANTEED if you did a test that measured flow at different distances away from the actual pump that these test results would be completely different! I've seen my tunze 6025 pump water across a 6' tank while my vortech mp40 barely creates surface aggitation after the 3' mark.

Lets open a can of worms here...How do you rate a skimmer??? How do you rate lights??? is there really an exact "This skimmer is rated for 300 gal." or "This light will work on a 75 gal. tank"...NO!

 

[MitchReef]

I finally gave up on my Koralias recently. They are in the box along with the Rios, Catalinas and such. I am using a noisy used MP40w Gen2 from a friend. It is loud but I like the water flow. Again, if funds were available I would probably be using Tunzes.

I just got tired of the Koralias breaking. I had 2 K4's that died, dumping stray current into my tank. I then tried one of the new "Evolution 1050" model. After 3 front nosecones breaking I gave up on that one. Not even 10 months old. This is a known issue that Hydor apparently chooses to ignore. They have replaced the nosecone each time, but they are still shipping identical poor quality replacements.

I am encouraged that Tunze has taken the high road, admitted an issue exists and is pursuing engineering avenues for making it right. It further reinforces my opinion that I will eventually use them.

 

[Dank Sinatra]

This is sad to hear, Roger is a great guy and stands behind his products and has always gone over and beyond what I would normally expect from a
Company.
What I find funny is why don't these law firms file against co's like Honda, toyota, ford, gm for things like there over exaggerated mpg claims, I have yet to own a car that got anywhere near the advertised mpg on the window sticker? Auto, Gas and oil co's can throw us under a bus but guy's like Roger get sued instead.
Imo... Just ain't rite!

I get an average of 4 to 5 more mpg than the quoted factory MPG sticker on my Tacoma.What are you driving?

 

[sreefer]

If you put a tunze 6305 and a vortech mp40 in the same tank and test them side by side...guaranteed you will see how much more flow the tunze does than the vortech...I don't think many people have used both products, and only if you have do you realize how different the flow patterns are. If you look at the test tunze did right after you can see the difference. The vortech produces a turbulent pattern while the tunze produces a linear pattern. Who says that the same exact test can accurately be used to measure both types of flow? GUARANTEED if you did a test that measured flow at different distances away from the actual pump that these test results would be completely different! I've seen my tunze 6025 pump water across a 6' tank while my vortech mp40 barely creates surface aggitation after the 3' mark.

Lets open a can of worms here...How do you rate a skimmer??? How do you rate lights??? is there really an exact "This skimmer is rated for 300 gal." or "This light will work on a 75 gal. tank"...NO!

Sir the issue here is the flow rate okay, the GPH. Test was already done by expert and Tunze already acknowledge and here is what they said "Study is correct for the flow produced by the actual pump itself and we will improve the pumps in a retrofittable manner“.
Here is the link read it for god sake. Tunze issues statement regarding the results of the propeller pump flow article
So Tunze clearly screwed up therefore they should take responsibility. Lets just wait for the outcome of the lawsuit. Maybe they can show the judge the youtube video abou the Tunze pump running a boat. How to Power a Boat with Aquarium Gear - YouTube

 

[macawmagic]

I read it...but if the flow from the pump creates even more flow due to the venturi effect that that flow shouldn't be added to the pump output total?

I really just want to know if there are any people on here that b4 this all happened were in love with their tunze's and after this now think their pump sucks??? I can honestly say even if on paper my tunze produces half the flow it says that it does...It still produces exactly what I needed it to and will be purchasing tunze's over vortech's any day of the week.

 

[shred5]

I wish people would quit putting their own spin on to what Tunze "agreed" to. First of all, they never agreed to the flow rates published in the original study. They only statement Tunze made was that they saw the same flow rates when using the same testing equipment and the same method. However, there is a big asterisk to that statement. Tunze later came out to doubt the accuracy of the test equipment and method used in the original study, stating that the equipment heavily favored pumps with more turbulent and less laminar flow. Because of this, they then set out to do a comparison of their pumps with their competitor's pumps in the video they released. The video successfully showed that Tunze Stream pumps pushed water farther while the competitor created more turbulence.

Moving on, Tunze never lied or falsely advertised their flow rates. They used two methods to arrive at their flow rate numbers for their pumps. They started with theoretical calculations that relied on the shape of the propeller and the speed at which it was rotating (RPM). After calculating these numbers, they performed a bag test. This test involves attaching a bag to the pump and timing how low it takes the bag to fill. The results of the bag fill method and the theoretical calculations were within +/-10% of each other. Both of these test methods are accepted within the industry, at least up until this point.

As for the advertised flow rates, if you look on a Tunze box they actually provide a range of flow instead of just one number. So technically, even if the pumps are putting out less than what they are supposed to, they are still safe from an advertising standpoint. The box and literature for the 6105 has a range of 792 to 3,434 USgal./h. The data from the study had the Tunze at 2358.2 gph, well within the range given by Tunze. This is also seen in the 6205 and 6305. I'm not using these numbers to justify anything other than the fact that technically they should be safe from someone claiming they aren't hitting advertised flow rates.

The other thing I wanted to bring up is the fact that EcoTech Marine did sponsor this study. Yes, Sanjay was a technical consultant, but only a consultant. Mike Sandford collected the data and performed the tests while interning at EcoTech Marine. On top of that, EcoTech Marine rented the test equipment and provided the aquarium to do all of the tests. Because of this, the entire study is biased to the point that its results should be doubted and they will not hold up in any sort of legal case. Since so many people are jumping on car analogies, do you think a study conducted by Chevrolet showing Ford vehicles to have a far poorer fuel economy than advertised would be well accepted by the public, people within the automotive industry, or people in the legal system? Of course not. And let me ask you this, what if Sanjay's name wasn't attached to the study? Would we still accept the data at face value or would we have our doubts?


Wrapping it up, I'm so surprised to see so many people jumping all over the "Let's bash Tunze into the ground" bandwagon after just one published experiment. The test wasn't independent, and the equipment and methods have been doubted by many engineers, hobbyists, and people in the aquarium industry. Instead of bashing Tunze, let the results of a real scientific study come out that doesn't just measure flow in one way, but a multitude of ways.

Another good post..

There are law suits all the time in this hobby. I still remember when Ron Shimik had did some tests on one of Julians products and Julian threatened to sue Ron to keep him from publishing the details.

I was involved in a ZeoVit thread along time ago during the early days of zeovit. We were basically trying to figure out how the system worked and what was in some of the products and were going to have them tested. The owner came in and threatened all of us involved in the thread with a lawsuit.

I think the most famous lawsuit was pfo which put them out of business.

I would hate to see that happen to tunze, They are an old company from the early days of reef keeping and have been on the cutting edge of reef keeping. If it were not for them allot of companies would not be as good as they are like Ecotech. They have made products that are lower power consumption and maximum efficency. The wide flow pumps would not be if it were not for tunze and there would not even be this discussion.


If it were not for Tunze there would not be a Ecotech marine.

Wonder what the authors of that article are thinking.. I do not think they wanted things to go this far.







Dave Polzin

 

[CJO]

Sir the issue here is the flow rate okay, the GPH. Test was already done by expert and Tunze already acknowledge and here is what they said "Study is correct for the flow produced by the actual pump itself and we will improve the pumps in a retrofittable manner“.
Here is the link read it for god sake. Tunze issues statement regarding the results of the propeller pump flow article
So Tunze clearly screwed up therefore they should take responsibility. Lets just wait for the outcome of the lawsuit. Maybe they can show the judge the youtube video abou the Tunze pump running a boat. How to Power a Boat with Aquarium Gear - YouTube

Are you reading the same articles as the rest of us or are you not comprehending the whole thing. Here is a telling exerpt from the article to which you linked, "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."

CJ

 

[AquaNerd1]

Sir the issue here is the flow rate okay, the GPH. Test was already done by expert and Tunze already acknowledge and here is what they said "Study is correct for the flow produced by the actual pump itself and we will improve the pumps in a retrofittable manner“.
Here is the link read it for god sake. Tunze issues statement regarding the results of the propeller pump flow article
So Tunze clearly screwed up therefore they should take responsibility. Lets just wait for the outcome of the lawsuit. Maybe they can show the judge the youtube video abou the Tunze pump running a boat. How to Power a Boat with Aquarium Gear - YouTube

You are still failing to acknowledge the fact that Tunze has expressed serious doubts about the original flow study. They have come out and stated explicitly that the original flow study was flawed. And if you want to start relying on experts, why don't we get one who specializes in water flow? Sanjay is a mechanical engineer. Im not trying to take away from his immense knowlege or all of the contributions he has made to the hobby, but there's a big difference in mechanical engineering and water flow engineering.

 

[Dave3112]

Hydraulic engineering? yes I'm a :nerd: Sorry I couldn't help myself. Now back to your regularly scheduled Mine is bigger than yours programming........

 

[cdness]

I hope noone jumps on board and supports this... The first thought I had on the article was doubts because it was commissioned by Ecotech marine and bashes their largest competitor Tunze... It had flaws from the start and I knew Tunze would be sending out a reply and other data. Anyone who blindly follows one company's research into a competitive company needs to remove the blinders. I don't use either as I have a closed loop, but I know the quality of Tunze and would lean their direction if I needed powerheads.

Also all you jumping on the car mileage bandwagon, My 96 Ranger with over 250,000 miles gets 37MPG on the highway and around 30 in town with the 2.3L 4Cylinder... That is WAY higher than the advertised mileage. And yes, I have a lead foot Remember the mileage stated on the stickers are also best case scenario calculated in a lab, not a calculated average of daily driving.

 

[tike]

Boy this is sure getting a lot of play on the net! My take, many moons ago I used the old tunze's, big bulky but worked great. I opted to the mp-40 and like it as well. Did tunze err in their calculation of flow....Yes, but it isn't worth a lawsuit. Nobody's tank was harmed in all the years the inflated flow rates were given so, what's the big deal? If, in some way people's tank/coral were harmed because of the false flow rates i could see grounds for lawsuit. Everyone's tank has performed just fine using these pumps, customer service has be great so let's just leave them alone and let them figure out their next move. Killing a good company for this reason is very irresponsible.

 

[shred5]

Boy this is sure getting a lot of play on the net! My take, many moons ago I used the old tunze's, big bulky but worked great. I opted to the mp-40 and like it as well. Did tunze err in their calculation of flow....Yes, but it isn't worth a lawsuit. Nobody's tank was harmed in all the years the inflated flow rates were given so, what's the big deal? If, in some way people's tank/coral were harmed because of the false flow rates i could see grounds for lawsuit. Everyone's tank has performed just fine using these pumps, customer service has be great so let's just leave them alone and let them figure out their next move. Killing a good company for this reason is very irresponsible.

I keep seeing how tunze errored in their calculations. People that say they did but do not say how they did. Tell me how they did, how were their test wrong? how were their calculations wrong?

Dave Polzin

 

[ja4207]

I wish people would quit putting their own spin on to what Tunze "agreed" to. First of all, they never agreed to the flow rates published in the original study. They only statement Tunze made was that they saw the same flow rates when using the same testing equipment and the same method. However, there is a big asterisk to that statement. Tunze later came out to doubt the accuracy of the test equipment and method used in the original study, stating that the equipment heavily favored pumps with more turbulent and less laminar flow. Because of this, they then set out to do a comparison of their pumps with their competitor's pumps in the video they released. The video successfully showed that Tunze Stream pumps pushed water farther while the competitor created more turbulence.

Moving on, Tunze never lied or falsely advertised their flow rates. They used two methods to arrive at their flow rate numbers for their pumps. They started with theoretical calculations that relied on the shape of the propeller and the speed at which it was rotating (RPM). After calculating these numbers, they performed a bag test. This test involves attaching a bag to the pump and timing how low it takes the bag to fill. The results of the bag fill method and the theoretical calculations were within +/-10% of each other. Both of these test methods are accepted within the industry, at least up until this point.

As for the advertised flow rates, if you look on a Tunze box they actually provide a range of flow instead of just one number. So technically, even if the pumps are putting out less than what they are supposed to, they are still safe from an advertising standpoint. The box and literature for the 6105 has a range of 792 to 3,434 USgal./h. The data from the study had the Tunze at 2358.2 gph, well within the range given by Tunze. This is also seen in the 6205 and 6305. I'm not using these numbers to justify anything other than the fact that technically they should be safe from someone claiming they aren't hitting advertised flow rates.

The other thing I wanted to bring up is the fact that EcoTech Marine did sponsor this study. Yes, Sanjay was a technical consultant, but only a consultant. Mike Sandford collected the data and performed the tests while interning at EcoTech Marine. On top of that, EcoTech Marine rented the test equipment and provided the aquarium to do all of the tests. Because of this, the entire study is biased to the point that its results should be doubted and they will not hold up in any sort of legal case. Since so many people are jumping on car analogies, do you think a study conducted by Chevrolet showing Ford vehicles to have a far poorer fuel economy than advertised would be well accepted by the public, people within the automotive industry, or people in the legal system? Of course not. And let me ask you this, what if Sanjay's name wasn't attached to the study? Would we still accept the data at face value or would we have our doubts?


Wrapping it up, I'm so surprised to see so many people jumping all over the "Let's bash Tunze into the ground" bandwagon after just one published experiment. The test wasn't independent, and the equipment and methods have been doubted by many engineers, hobbyists, and people in the aquarium industry. Instead of bashing Tunze, let the results of a real scientific study come out that doesn't just measure flow in one way, but a multitude of ways.

After reading that paragraph I no longer read any of your posts. That has got to be the most ridiculous defense I've heard in awhile!

As far as your explanation and defense to Tunze unfortunately Tunze doesn't agree with you. Sounds like to me you are half hoping this was their position and response and half full of crap. Sorry to put it so blunt but your wrong, wrong and wrong.

Please read my post regarding false advertisement.

 

[ja4207]

You are still failing to acknowledge the fact that Tunze has expressed serious doubts about the original flow study. They have come out and stated explicitly that the original flow study was flawed. And if you want to start relying on experts, why don't we get one who specializes in water flow? Sanjay is a mechanical engineer. Im not trying to take away from his immense knowlege or all of the contributions he has made to the hobby, but there's a big difference in mechanical engineering and water flow engineering.

Proof of this???? Didn't think so!

 

[bct15]

Aquanerd, my undergrad was mechanical engineering with a focus in fluid dynamics, computational and the otherwise...my graduate study is more materials and mathematical based though. But mechanical engineers may be qualified to discuss the topic of flow depending on their area of emphasis.

Shred, what are you trying to ask? Who do you want to know made an error? The method that the study used to estimate the flow appears to not be able to accurately estimate laminar directional flow, or turbulence in the flow may introduce a huge amount of biased to the measurement device (just one theory).

 

[revhtree]

Let's have a great debate but don't get mad and offensive.

 

[ja4207]

I'll tone it down!

 

[bct15]

After reading that paragraph I no longer read any of your posts. That has got to be the most ridiculous defense I've heard in awhile!

As far as your explanation and defense to Tunze unfortunately Tunze doesn't agree with you. Sounds like to me you are half hoping this was their position and response and half full of crap. Sorry to put it so blunt but your wrong, wrong and wrong.

Please read my post regarding false advertisement.

The first couple paragraphs are actually very informative and explain that there is most likely some errors in the testing procedure. The two main powerheads in discussion in the paper produce two vastly different types of flow, therefor making it difficult to compare the two using the same testing technique. Anybody with an understanding of fluid dynamics will understand this, and this is why, like myself, many engineers and scientist doubt the validity of the often cited report. To many people who read this report suddenly think they are flow experts because they know how to read a published number but do not know where the numbers actually came from. To accurately estimate the flow produced by these powerheads, the flow should be calculated in at least three different ways, then results should be compared and flow numbers can be estimated takin into account various flow conditions.

Tunze has come out and publicly stated that they have found errors in the original experimentation technique. People need to sit back, take a deep breath and see how everything plays out...

 

[ja4207]

The first couple paragraphs are actually very informative and explain that there is most likely some errors in the testing procedure. The two main powerheads in discussion in the paper produce two vastly different types of flow, therefor making it difficult to compare the two using the same testing technique. Anybody with an understanding of fluid dynamics will understand this, and this is why, like myself, many engineers and scientist doubt the validity of the often cited report. To many people who read this report suddenly think they are flow experts because they know how to read a published number but do not know where the numbers actually came from. To accurately estimate the flow produced by these powerheads, the flow should be calculated in at least three different ways, then results should be compared and flow numbers can be estimated takin into account various flow conditions.

Tunze has come out and publicly stated that they have found errors in the original experimentation technique. People need to sit back, take a deep breath and see how everything plays out...

Really show me thier public statement regarding that.

As far as people believing they are flow experts, I agree! Have you read the original report at all? Honest question.... In my opinion you haven't nor has Shred based on your responses.

 

[dougers31]

Also all you jumping on the car mileage bandwagon, My 96 Ranger with over 250,000 miles gets 37MPG on the highway and around 30 in town with the 2.3L 4Cylinder... That is WAY higher than the advertised mileage. And yes, I have a lead foot Remember the mileage stated on the stickers are also best case scenario calculated in a lab, not a calculated average of daily driving.

I know when I purchased my 2006 honda civic it stated that it could get 40mpg hwy.... most I have gotten was 38 and now 35(I use full syn. oil now) is about it. I do believe there was a lawsuit or some government(epa?) mandate that made them(and other manufacturers) adjust their mpg estimates a year or so later. I do know that the same(same specs and body style) model civic went from 40mpg to either 36 or 38 mpg a year or so later.