coralmadness
Member
Just curious if anyone still uses eductors in their tank? If so how well does it work for you?
Eductors
- Thread starter coralmadness
- Start date
sicksnoopy71
Member
I have never even heard of them. Nice to be informed, you learn something every day. I will be doing some research on them to see how I may get benefits from using one.
I too am just reading about them... just read the below from a google search ...
Does this go against the laws of physics?
or am I missing something...
Tank Eductors - $22.99 : AQUAFINATIC - The Worlds Reef In Your Aquarium
Does this go against the laws of physics?
or am I missing something... Tank Eductors - $22.99 : AQUAFINATIC - The Worlds Reef In Your Aquarium
theplantman
Active Member
I just read it as well. Think of it as a ceiling fan without blades or a jet engine. Water from your pump is compressed through a small opening, increasing its velocity, when it exits the smaller nozzle, there are vents where the nozzle widens. When water passes through this space it creates suction that pulls water from the display in through those vents mixing display water with the return water thus increasing the flow through the larger end of the nozzle.
Remember the old road runner cartoons, he went by so fast he drug debris in his wake.....same principle but in real life.... at least that's my interpretation...beep beep:scram:
Remember the old road runner cartoons, he went by so fast he drug debris in his wake.....same principle but in real life.... at least that's my interpretation...beep beep:scram:
LOL @ Mike.... that's pretty accurate....
One thing I've heard over the years is they need to be "tweaked" to be effective and they have to remain clean. Once they get a little "fuzzy/dirty" they become very inefficient.
I've always been tempted to try one for myself but never have yet.
One thing I've heard over the years is they need to be "tweaked" to be effective and they have to remain clean. Once they get a little "fuzzy/dirty" they become very inefficient.
I've always been tempted to try one for myself but never have yet.
theplantman
Active Member
If you think about it, most of our powerheads work on this principle, you have a small impeller pushing water out the opening but there are slots all through the frame to allow more display water to be added to it. Not quite the same design but similar function. If you ever get ahold of one put it in a bucket of rodi drop some food coloring next to the intakes and you will see it at work.
I get the increased pressure part... like a garden hose with a nozzle attached... but when I add the nozzle to the hose, it does not triple my water going through the hose... maybe I am reading it wrong...
"triple your beneficial water circulation"
"triple your beneficial water circulation"
theplantman
Active Member
the part you are missing is the added water volume being sucked in from the display. with the hose scenario you are increasing velocity through the nozzle but not adding any additional water volume. Now if you were to drop that hose in the water and jet it though a little larger but short pvc pipe set about 1/2-1" in front of it, the stream coming out of the nozzle would pull additional water in with it. Pressure would be reduced but volume of water through the pvc would be increased, creating greater circulation.
coralmadness
Member
I think Im going to give it a try and see how it works out.
theplantman
Active Member
use some food coloring dropped next to the stream before it goes into the pvc and you will see it sucked in.
Thanks for the replies... Coralmadness let us know how it does for you 
just read this...
How an eductor works is a little more complicated, and in short, the performance of an eductor revolves around the Venturi principle.
Water flowing axially into and then through the eductor creates a relative negative pressure at holes placed in the wall of the device. This negative pressure causes more flow to enter the eductor at these holes or ports, thereby creating a net increase in flow exiting the device compared to what entered at the beginning. Of course, conservation of mass and volume apply, so the water axially entering the eductor initially, plus the water pulled in through the side ports, equals the water discharged axially at the end of the eductor.
just read this...
How an eductor works is a little more complicated, and in short, the performance of an eductor revolves around the Venturi principle.
Water flowing axially into and then through the eductor creates a relative negative pressure at holes placed in the wall of the device. This negative pressure causes more flow to enter the eductor at these holes or ports, thereby creating a net increase in flow exiting the device compared to what entered at the beginning. Of course, conservation of mass and volume apply, so the water axially entering the eductor initially, plus the water pulled in through the side ports, equals the water discharged axially at the end of the eductor.
theplantman
Active Member
Try this read Glenn. It has a diagram and a link for saltwater enthusiast for pennductors. YAY 
Pretty funny DIY version as well.
MIXING EDUCTORS
Pretty funny DIY version as well.MIXING EDUCTORS