[nagukush]

Hi Friends !

I hope all is well and great !

I just finished cleaning my Eheim 2217 (the filter media, impeller etc) and I'm surprised how much the outflow is increased !!!

I'm using the Eheim Wide jet pipe to return the water from the filter, to the tank, which creates a single jet of water at the water surface. Now due to this increased outflow (caused by the filter cleaning), my Tank's water is getting really distrubed.

Just wanted to know if I can use the Quick Disconnect Valves at the Output End, to reduce the flow of the Filter ? Will any back pressure be caused because of this and will it harm my filters motor in the long run ?

Will this reduce the filters efficiency in any way ?

Also if you can kindly have a look at this link http://www.eheim.de/eheim/inhalte/index.jsp?key=liniendetail_27655_ehen

there is also a Shut-Off Valve available from the eheim people, which (as mentioned i the website) says - "The water cycle in the hose system can be conveniently interrupted and regulated with the EHEIM shut-off valve"

Kindly guide me if its safe to control the outflow using this valve...
Thanks and Regards
Kush

 

[vancat]

I would be wary of doing that. Why not use a spray bar return to spread out the strong outflow? How big is your tank?

 

[nagukush]

Its a 4 Feet Acrylic Tank and because of the design (frames, hood etc) its not possible to mount the spray bar. Also there is a 3d Background attached at the back..

Kindly guide me... is there a risk in doing this ?

 

[vancat]

I don't know, but let's wait for someone else to chime in. Bryce perhaps?

BTW I used to have a spray bar mounted diagonally on a short side of the tank. I had it that way for many years but just moved it.

 

[BryceM]

Did somebody call?

With centrifugal pumps (like the Eheim) it is perfectly fine to partially block the outflow. This won't have the slightest negative effect apart from decreasing flow. Just be sure you don't block the inlet pipe.

Now, I really doubt that the disturbance of the substrate or the billowing clouds of debris will last for more than a day. The filter is just doing its job, moving stuff up into the water column where it will be quickly removed.

 

[nagukush]

So is the 2217's pump Centrifugal ? So If I block the outlet to reduce the flow - my filter will be safe, even in the longrun ? Wont the back-pressure cause any problems, anytime ?

 

[BryceM]

Partially closing the outflow valve does nothing to damage a centrifugal pump. The actual effect is to move the operating point to a new position on the pump curve. There really isn't any "back pressure".

No problem at all - not today, not in a week, not in a 100 years.

BTW, I did this once and the Eheim "double-tap" valve started leaking in the partially closed position. The resultant flood was less agreeable than the extra flow I had.

 

[nagukush]

Partially closing the outflow valve does nothing to damage a centrifugal pump. The actual effect is to move the operating point to a new position on the pump curve. There really isn't any "back pressure".

No problem at all - not today, not in a week, not in a 100 years.

BTW, I did this once and the Eheim "double-tap" valve started leaking in the partially closed position. The resultant flood was less agreeable than the extra flow I had.

Hi there !

Thanks a lot for the kind reply and for guiding me... So there is a risk of the Double-Taps leaking sometime ? That would be really bad...

Just wanted to request you to kindly advice regarding the "partially closed position" - does this mean that the even if the taps start leaking sometime, will the open position also leak ?

Kindly guide me a little here...
Thanks a lot !
REgards and Care
Kush

 

[BryceM]

I had this happen once on one particular filter. Other times & in other places it's been perfectly fine.

That valve that did leak was just fine when I opened it all the way.

 

[rich815]

Won't partially closing the outflow of a Quick Connect create a much stronger, smaller outflow?

 

[BryceM]

Someday I'll put together an article on basic fluid mechanics. Almost all of hte basic principles are confusing at first.

Flow is measured in gallons per hour or cubic yards per fortnight. It is the rate at which fluid is moving.

Velocity describes the actual speed and direction of fluid movement. This is measured in miles per hour, feet per second, or furlongs per fortnight.

For a given size pipe (or tube) velocity and flow are proportional. Cut the area of the pipe in half and velocity must double to acheive the same flow.

By "stronger outflow" I don't know what you mean. If you slow down the rate of flow in a pipe by partially closing a valve, the velocity decreases too.

A nozzle on a garden hose might appear to increase the "strength" of the stream but what actually happens is that you restrict the flow enough to permit the original source water pressure to be maintained. The velocity of the small jet is therefore relatively high, especially when compared to the velocity of the water in the rest of the garden hose.

 

[nagukush]

Thanks for the kindness and for guiding me... Really grateful

Thanks again !
Regards
Kush