Eheim Tells me a bigger hose is bad??

mnestroy · 11/02/2006, 01:22 PM

So I recently purchased an Eheim 1250 pump for my sump... and I was under the impression that u want to doulbe the size of the outlet...

I emailed them asking about increasing the size and this was their response

Any comments?

---------------------------------------------
Dear Mike,

The EHEIM 1250 pump uses the EHEIM 4004940 hose which is 12mm inside diameter and 16mm outside diameter. Increasing the size of the hose will decrease the pressure and also the flow of the pump.

Please do not hesitate to contact me if you require further assistance.

Yours truly,

Ernesto Cedeno
Technical Support
support@eheim.com
http://www.eheim.com/http://www.eheim.com/
EHEIM North America Reg.

Rascal1371 · 11/02/2006, 01:28 PM

I think they are mistaken in their terminology. If they had said that increasing the diameter would decrease the VELOCITY of the flow, I would agree. The total flow rate (defined as volume of water per unit of time) should increase. I am sure there is a point of diminishing returns where the diameter would be too great and the pump might do no more than circulate the water inside the pipe (imagine a pipe diameter of 2 feet for an extreme example), but I don't think you will run into that probelm just by doubling the diameter.

Only way to tell for sure it is to try it both ways and see what happens.

MJAnderson · 11/02/2006, 01:32 PM

Speaking from rumor (i read this before on RC), MAG pumps work best when you double the size of the output. I was told you don't need to with Eheim pumps.

RichConley · 11/02/2006, 01:35 PM

Quote:

Originally posted by MJAnderson
Speaking from rumor (i read this before on RC), MAG pumps work best when you double the size of the output. I was told you don't need to with Eheim pumps.

The increase with larger plumbing isnt as drastic, but its still there. Bigger plumbing is always better...

mnestroy · 11/02/2006, 01:58 PM

Might be a stupid question, but if the pump will function better with a larger size hose, why wouldn't they just make the outflow that size to start off with?

Gooli · 11/02/2006, 02:01 PM

i've been using eheim pumps internally and externally...u do not need to increase the size of the pipe (this isnt a MAG pump)

RichConley · 11/02/2006, 02:24 PM

Quote:

Originally posted by mnestroy
Might be a stupid question, but if the pump will function better with a larger size hose, why wouldn't they just make the outflow that size to start off with?

Changing the size of the outlet of the pump has additional effects that changing the hose size doesnt

RichConley · 11/02/2006, 02:24 PM

Quote:

Originally posted by gooliver
i've been using eheim pumps internally and externally...u do not need to increase the size of the pipe (this isnt a MAG pump)

you dont NEED to increase on ANY pump. But on ALL pumps you will see an increase in flow by increasing pipe size.

kslick · 11/02/2006, 07:37 PM

I would listen to thier advice, Eheim is a great company, so why question them.

SDguy · 11/02/2006, 08:10 PM

Quote:

Originally posted by kslick
I would listen to their advice, Eheim is a great company, so why question them.

I agree, but at the risk of sounding suspicious, they're basically saying to use THEIR brand of hose. That stuff is more than double generic hose...
]
Don't get me wrong...if my pump company made my own brand of tubing, I'd only recommend it too

jeffgp · 11/02/2006, 08:25 PM

for my return i have a rio 2100 and output is 3/4 and im using a 1" pipe and then 'T' for dual into my tank and it works great

mnestroy · 11/02/2006, 08:32 PM

So,

If I dont want the hasle of adapters etc, what size utub should i order?

sjm817 · 11/02/2006, 08:34 PM

IME, Eheims tend to handle head pressure a lot better than other submersibles such as Mags. Large plumbing makes a huge difference on a Mag, not all that much on an Eheim.

jeffgp · 11/02/2006, 08:55 PM

if it has 3/4 just keep that or i allways go one size larger like 1"

11/02/2006, 01:22 PM	#1
mnestroy Registered Member Join Date: Apr 2006 Location: Aurora, IL Posts: 2,216	Eheim Tells me a bigger hose is bad?? So I recently purchased an Eheim 1250 pump for my sump... and I was under the impression that u want to doulbe the size of the outlet... I emailed them asking about increasing the size and this was their response Any comments? --------------------------------------------- Dear Mike, The EHEIM 1250 pump uses the EHEIM 4004940 hose which is 12mm inside diameter and 16mm outside diameter. Increasing the size of the hose will decrease the pressure and also the flow of the pump. Please do not hesitate to contact me if you require further assistance. Yours truly, Ernesto Cedeno Technical Support support@eheim.com http://www.eheim.com/http://www.eheim.com/ EHEIM North America Reg.

11/02/2006, 02:01 PM	#6
Gooli Registered Member Join Date: Jun 2004 Location: West Los Angeles Posts: 3,746	i've been using eheim pumps internally and externally...u do not need to increase the size of the pipe (this isnt a MAG pump) __________________ "Beer is living proof that God loves us and wants us to be happy. " - Benjamin Franklin Current Tank Info: 180g SPS

11/02/2006, 08:25 PM	#11
jeffgp Registered Member Join Date: Jan 2006 Location: milwaukee Posts: 625	for my return i have a rio 2100 and output is 3/4 and im using a 1" pipe and then 'T' for dual into my tank and it works great __________________ (Member of the Gem Tang Rider Posse) check my red house Current Tank Info: reef tank

11/02/2006, 08:34 PM	#13
sjm817 On Yer left! Join Date: Sep 2004 Location: Northern VA Posts: 18,777	IME, Eheims tend to handle head pressure a lot better than other submersibles such as Mags. Large plumbing makes a huge difference on a Mag, not all that much on an Eheim. __________________ - Scott

11/02/2006, 08:55 PM	#14
jeffgp Registered Member Join Date: Jan 2006 Location: milwaukee Posts: 625	if it has 3/4 just keep that or i allways go one size larger like 1" __________________ (Member of the Gem Tang Rider Posse) check my red house Current Tank Info: reef tank

11/02/2006, 01:28 PM	#2
Rascal1371 Premium Member Join Date: May 2006 Location: Annandale, VA Posts: 101	I think they are mistaken in their terminology. If they had said that increasing the diameter would decrease the VELOCITY of the flow, I would agree. The total flow rate (defined as volume of water per unit of time) should increase. I am sure there is a point of diminishing returns where the diameter would be too great and the pump might do no more than circulate the water inside the pipe (imagine a pipe diameter of 2 feet for an extreme example), but I don't think you will run into that probelm just by doubling the diameter. Only way to tell for sure it is to try it both ways and see what happens.

11/02/2006, 01:32 PM	#3
MJAnderson Premium Member Join Date: May 2006 Location: East Bay, CA Posts: 2,633	Speaking from rumor (i read this before on RC), MAG pumps work best when you double the size of the output. I was told you don't need to with Eheim pumps.

11/02/2006, 01:58 PM	#5
mnestroy Registered Member Join Date: Apr 2006 Location: Aurora, IL Posts: 2,216	Might be a stupid question, but if the pump will function better with a larger size hose, why wouldn't they just make the outflow that size to start off with?

11/02/2006, 07:37 PM	#9
kslick Registered Member Join Date: Mar 2005 Location: Colorado Posts: 253	I would listen to thier advice, Eheim is a great company, so why question them.

11/02/2006, 08:32 PM	#12
mnestroy Registered Member Join Date: Apr 2006 Location: Aurora, IL Posts: 2,216	So, If I dont want the hasle of adapters etc, what size utub should i order?