Tunze pumps found to have flow problems

[canadianreefer]

Interesting article:
http://www.advancedaquarist.com/2011/7/aafeature">http://www.advancedaquarist.com/2011/7/aafeature</a>

Response from Tunze on July 13th:
[IMG]http://www.advancedaquarist.com/blog/tunze-issues-press-release">http://www.advancedaquarist.com/blog/tunze-issues-press-release</a>

 

[rbredding]

they dont have flow problems...

There are now more advanced ways to measure total movement created by a pump, which were not previously taken into account when measuring flow..

Which is to say that if they are shown to deliver 1500gph flow, they will fill a bag with 1500 gallons of water in one hour... (or within 10% of that volume, anyway)
There are tens of thousands of very successful aquariums in the world running Tunze pumps..

Ecotech used a more advanced method to measure total water movement within an aquarium (not just at the pump, as previously used/measured).


the more comprehensive method of evaluating water movement will likely LOWER the "flow needs" used when designing a system (I would think)..

 

[canadianreefer]

No question that Tunze are used in many successful aquariums.

However the bag method was only used to measure the lower GPH units. The higher GPH units were not measured. This study revealed that the current design restricted the flow entering and exiting the units. I would consider that a flow problem. And Tunze acknowledged this in their response that I linked.

I am not suggesting anybody get rid of their unit but to simply watch for when Tunze releases their retrofit that will address the issue. They said that they will attempt to release it within 6 months.

 

[grouper therapy]

Rbredding;667122 wrote: they dont have flow problems...

There are now more advanced ways to measure total movement created by a pump, which were not previously taken into account when measuring flow..

Which is to say that if they are shown to deliver 1500gph flow, they will fill a bag with 1500 gallons of water in one hour... (or within 10% of that volume, anyway)
There are tens of thousands of very successful aquariums in the world running Tunze pumps..

Ecotech used a more advanced method to measure total water movement within an aquarium (not just at the pump, as previously used/measured).


the more comprehensive method of evaluating water movement will likely LOWER the "flow needs" used when designing a system (I would think)..

Exactly! This is the most advanced test and/or method to date but as the researchers even stated that it was experimental and there are theories involved. The effect that different flow patterns has on the water around it is still not fully understood. Tunze was producing their pumps long before most of the others were even in the market so I would imagine that their rating assessment was as accurate as the testing methods available to them at the time. It is quite obvious that they were nowhere near accurate in their calculations and that others produce more flow, To say that they had a flow problem would be the same as saying that the mp 10 did as well . Before this test I can't recall anyone complaining about the amount of flow that the tunzes produced . not even the ones who switched to Vortechs. They did notice a difference between them but never that Tunzes were not enough.

Edit:

CanadianReefer;667200 wrote: No question that Tunze are used in many successful aquariums.

However the bag method was only used to measure the lower GPH units. The higher GPH units were not measured. <u> This study revealed that the current design restricted the flow entering and exiting the units. I would consider that a flow problem. </em></u> And Tunze acknowledged this in their response that I linked.

I am not suggesting anybody get rid of their unit but to simply watch for when Tunze releases their retrofit that will address the issue. They said that they will attempt to release it within 6 months.

Based on that logic then all pumps with any guard has a flow problem .