External pump question?

scooter413 · 06/20/2014, 03:17 PM

I have an external pump with a 1 1/2 inch inlet. What problems will I encounter reducing down to a 1" to fit my bulkhead on the sump?

billdogg · 06/20/2014, 05:18 PM

The input to the pump or the output? If it is the pipe going in to the pump you cannot reduce the size without causing it to cavitate. If it's the return, you'll reduce the flow but otherwise will be ok.

scooter413 · 06/20/2014, 05:41 PM

It is the pipe going into the pump.

viper12775 · 06/20/2014, 06:40 PM

it depends on the pump some pumps can be throttled down on the intake to reduce flow

scooter413 · 06/20/2014, 06:48 PM

So how would I know. It's a sequence 1000 pump that's pushing 3300 gallons per hour. I need to slow the flow so I was going to put a ball valve in. I don't want to drill for a 1" bulkhead when I need a 1 1/2".

Mark Bianco · 06/20/2014, 08:58 PM

According to Reeflo Never restrict the incoming flow to the pump, if you need to restrict flow the a ball valve on the output is fine. It is a good idea to have a shutoff but leave it full open. That being said also a good rule of thumb is to make sure the length of the inlet pipe should be 10X the diameter of the pipe

scooter413 · 06/21/2014, 08:34 AM

Great info. I will just wait and order the correct bulkhead. Thanks to all for the information.

sowildpaul · 06/21/2014, 12:30 PM

Quote:

Originally Posted by Mark Bianco

According to Reeflo Never restrict the incoming flow to the pump, if you need to restrict flow the a ball valve on the output is fine. It is a good idea to have a shutoff but leave it full open. That being said also a good rule of thumb is to make sure the length of the inlet pipe should be 10X the diameter of the pipe

What? For example, a diameter of the pipe is 1" so the length of the inlet pipe should be at least 10 feet? If so, why? I have never heard of it.

pmrossetti · 06/21/2014, 12:34 PM

Quote:

Originally Posted by sowildpaul

What? For example, a diameter of the pipe is 1" so the length of the inlet pipe should be at least 10 feet? If so, why? I have never heard of it.

That would be 10 inches, no?

sowildpaul · 06/21/2014, 01:07 PM

Quote:

Originally Posted by pmrossetti

That would be 10 inches, no?

Oops, my bad. Yeah, I mean 10 inches but still why? I see many return pumps are so close to the bulkheads at the sumps (less than 10 inches). I am curious what's the purpose of 10 inches or longer for 1-1.5" inlet pipe?

pmrossetti · 06/21/2014, 05:44 PM

Quote:

Originally Posted by sowildpaul

Oops, my bad. Yeah, I mean 10 inches but still why? I see many return pumps are so close to the bulkheads at the sumps (less than 10 inches). I am curious what's the purpose of 10 inches or longer for 1-1.5" inlet pipe?

I'm thinking it's to prevent any bubbles from entering or to reduce any turbulence.

06/20/2014, 03:17 PM	#1
scooter413 Registered Member Join Date: Jan 2014 Posts: 14	External pump question? I have an external pump with a 1 1/2 inch inlet. What problems will I encounter reducing down to a 1" to fit my bulkhead on the sump?

06/20/2014, 05:18 PM	#2
billdogg Registered Member Join Date: Apr 2008 Location: Grove City, Ohio Posts: 10,806	The input to the pump or the output? If it is the pipe going in to the pump you cannot reduce the size without causing it to cavitate. If it's the return, you'll reduce the flow but otherwise will be ok. __________________ I'll try to be nice if you try to be smarter! I can't help that I grow older, but you can't make me grow up! Current Tank Info: 120 mixed reef with 40b sump, RO 150 skimmer, AI Sol Blue x 2, and a 60g Frag Tank with 100g rubbermaid sump. 2 x Kessil A360w lights, BM curve 5 skimmer

06/20/2014, 05:41 PM	#3
scooter413 Registered Member Join Date: Jan 2014 Posts: 14	It is the pipe going into the pump.

06/20/2014, 06:40 PM	#4
viper12775 Registered Member Join Date: Sep 2002 Location: clearwater fl Posts: 1,151	it depends on the pump some pumps can be throttled down on the intake to reduce flow

06/20/2014, 06:48 PM	#5
scooter413 Registered Member Join Date: Jan 2014 Posts: 14	So how would I know. It's a sequence 1000 pump that's pushing 3300 gallons per hour. I need to slow the flow so I was going to put a ball valve in. I don't want to drill for a 1" bulkhead when I need a 1 1/2".

06/20/2014, 08:58 PM	#6
Mark Bianco In Memoriam Join Date: Nov 2011 Location: Infinity and Beyond Posts: 2,445	According to Reeflo Never restrict the incoming flow to the pump, if you need to restrict flow the a ball valve on the output is fine. It is a good idea to have a shutoff but leave it full open. That being said also a good rule of thumb is to make sure the length of the inlet pipe should be 10X the diameter of the pipe

06/21/2014, 08:34 AM	#7
scooter413 Registered Member Join Date: Jan 2014 Posts: 14	Great info. I will just wait and order the correct bulkhead. Thanks to all for the information.