Submersible Return Pump Platform?

zombot · 12/17/2013, 05:19 AM

Hey guys,

I was wondering because i've come across it a few times in custom sumps once in awhile of custom sumps that have like a platform/stand like a protein skimmer stand but for their return pump. I've also seen like a free floating/built in shelf for one as well.

I know it's not a vast difference but would this also reduce head pressure loss?

I'm building a custom sump and thought about including this.

Thoughts? Queries? Doubtful points?

Mark... · 12/17/2013, 05:53 AM

More importantly it would reduce an overflow situation because of less potential volume that could be sent to the display tank.

BoxesOfTheSea · 12/17/2013, 07:23 AM

Head pressure reduction would be minimal (just a couple of inches) but it would definitely reduce the potential overflow volume.

Ikserk · 12/17/2013, 10:03 AM

in the interest of playing devils advocate....

it would also mean less insurance on your return pump running dry. This can be largely mitigated by an auto-top-off setup.

on the positive side, it may reduce the vibration being transferred from the pump to the sump walls/floor and then to the stand resulting in a quieter pump. The rubber mats used to silence these vibrations may be more effective if there is another material in between the pump and the mat (this so called pump stand that you are proposing)

jerpa · 12/17/2013, 10:17 AM

It will have no effect on head pressure. The vertical head is measured from the water line in the sump to the water line of the display. As stated above the shelf/platform does increase the potential of the pump running dry and I would rather prevent tank overflows in other ways. I doubt it will do much for vibration unless it sits on a silicone mat.

mcgyvr · 12/17/2013, 11:25 AM

You want it as low as possible.. Not higher..
Why..well with most systems upon startup the water in that area will tend to drop far below the normal water line until the return kicks in fully and allows it to fill back up..
You can run the pump dry if its too high..

On mine the water goes down a good 6-8 inches in that section before returning to normal after startup..

SGT_York · 12/17/2013, 12:25 PM

No affect on head pressure, none at all jerpa has it spot on.

zombot · 12/18/2013, 12:21 AM

In reguards to the head height of the pump?

barjam · 12/18/2013, 01:53 PM

Quote:

Originally Posted by zombot

In reguards to the head height of the pump?

Yes, the pump height has zero to do with head. You measure head from the height of the water in the sump. Where the pump is makes no difference.

If your return pump could do 1000 gph at zero head you would get 1000gph at the surface and 1000gph if it were at the bottom at 20 feet pool (with a pipe to the surface, measuring flow at the surface).

As far as your overall question there is zero advantage to moving the pump higher in the sump other than dampening vibrations. Don't need much height there.

El Porker · 01/04/2014, 12:26 PM

There are two types of pressure associated with a pump, suction and discharge pressure.

Suction pressure is determined by the height of the water column in relation to the suction side of the pump.

Discharge pressure is determined by the amount of suction head, +/- impeller clearance and height of discharge column.

The higher a pump has to push a column of water the more pressure it takes to overcome the height.

Most industrial pumps have a "pump curve" that shows these variables and will show how to setup a pump to run at optimal performance.

Since 1 psi equals 27.7 inches of water column, placement of the pump a few inches off the bottom of the sump floor would not reduce the discharge pressure enough to really matter.

I think the advantage to having the pump on a stand would be lessening the ability of the pump to pick up sediment or debris from the bottom of the sump.

12/17/2013, 05:19 AM	#1
zombot Registered Member Join Date: Mar 2013 Posts: 72	Submersible Return Pump Platform? Hey guys, I was wondering because i've come across it a few times in custom sumps once in awhile of custom sumps that have like a platform/stand like a protein skimmer stand but for their return pump. I've also seen like a free floating/built in shelf for one as well. I know it's not a vast difference but would this also reduce head pressure loss? I'm building a custom sump and thought about including this. Thoughts? Queries? Doubtful points?

12/17/2013, 05:53 AM	#2
Mark... Registered Member Join Date: May 2013 Location: Jersey Shore Posts: 617	More importantly it would reduce an overflow situation because of less potential volume that could be sent to the display tank. __________________ The solution, to pollution, is dilution... Current Tank Info: 180

12/17/2013, 10:17 AM	#5
jerpa Registered Member Join Date: Apr 2011 Location: Pittsburgh Posts: 2,174	It will have no effect on head pressure. The vertical head is measured from the water line in the sump to the water line of the display. As stated above the shelf/platform does increase the potential of the pump running dry and I would rather prevent tank overflows in other ways. I doubt it will do much for vibration unless it sits on a silicone mat. __________________ Jer Current Tank Info: 40b basement sump, 40b refugium, 30g frag

12/17/2013, 11:25 AM	#6
mcgyvr Registered Member Join Date: Sep 2003 Location: North Carolina Posts: 20,050	You want it as low as possible.. Not higher.. Why..well with most systems upon startup the water in that area will tend to drop far below the normal water line until the return kicks in fully and allows it to fill back up.. You can run the pump dry if its too high.. On mine the water goes down a good 6-8 inches in that section before returning to normal after startup.. __________________ Who me?

12/17/2013, 07:23 AM	#3
BoxesOfTheSea Registered Member Join Date: Jul 2013 Posts: 165	Head pressure reduction would be minimal (just a couple of inches) but it would definitely reduce the potential overflow volume.

12/17/2013, 10:03 AM	#4
Ikserk Registered Member Join Date: Jun 2013 Posts: 72	in the interest of playing devils advocate.... it would also mean less insurance on your return pump running dry. This can be largely mitigated by an auto-top-off setup. on the positive side, it may reduce the vibration being transferred from the pump to the sump walls/floor and then to the stand resulting in a quieter pump. The rubber mats used to silence these vibrations may be more effective if there is another material in between the pump and the mat (this so called pump stand that you are proposing)

12/17/2013, 12:25 PM	#7
SGT_York Registered Member Join Date: Sep 2012 Location: Washington State Posts: 1,746	No affect on head pressure, none at all jerpa has it spot on.

12/18/2013, 12:21 AM	#8
zombot Registered Member Join Date: Mar 2013 Posts: 72	In reguards to the head height of the pump?

01/04/2014, 12:26 PM	#10
El Porker Registered Member Join Date: Dec 2013 Posts: 1	There are two types of pressure associated with a pump, suction and discharge pressure. Suction pressure is determined by the height of the water column in relation to the suction side of the pump. Discharge pressure is determined by the amount of suction head, +/- impeller clearance and height of discharge column. The higher a pump has to push a column of water the more pressure it takes to overcome the height. Most industrial pumps have a "pump curve" that shows these variables and will show how to setup a pump to run at optimal performance. Since 1 psi equals 27.7 inches of water column, placement of the pump a few inches off the bottom of the sump floor would not reduce the discharge pressure enough to really matter. I think the advantage to having the pump on a stand would be lessening the ability of the pump to pick up sediment or debris from the bottom of the sump.