Return plumbing question

[RemainVayne]

I am going to use 2 Jebao dcp-10000 return pumps and my tank will have 1" return holes. The pumps output is 1.75", so would it be best to run the 1.75" pipe size as far as possible and neck down to my 1" bulkhead close to it? Or should I use the included 1" pump output adapter straight off the pump and run 1" piping all the way to my return bulkheads?

This is my first sump build and want to make sure I'm plumbing it correctly.

 

[aotechs]

It may be easier to use the reducer provided with the pump. Any chance you could enlarge the returns?

 

[Oughtsix]

Theoretically 1.75" return line stopped down to 1" at the bulkhead would provide minimal extra flow. As one that over engineers everything and worries about every extra drop of flow I went with running 1" hard line (pvc pipe) for my entire return. The extra few drops of flow wasn't worth the extra complexity and much higher expense to me.

P.S. There is no commonly available 1.75 plumbing that I am aware of... so you would probably have to go with 1.5" at best. I recommend going with 1".

 

[RemainVayne]

I was wrong as the plumbing is 1.25", so I'll try to run that as far as possible before necking down.

Of course, now I'm looking at going flex pipe instead of PVC as it just seems so much simpler. Also, it's tough trying to work out how to divert the two main return plumbing lines into the four total return bulkheads.

 

[Oughtsix]

Flexible PVC pipe has very minimal more resistance than hard PVC. A spiral wound tubing has much greater additional resistance than flexible PVC. If you are going with a spiral wound tubing the extra .25" will help a noticeable amount in keeping the flow up.

Flexible tubing is definitely easier to work with than hard PVC and even flexible PVC.

Splitting flow with a Y is pretty easy if you decide to go that route.

Get a 1.25" Y and put it close to the pump. On the 2 outlets from the Y put some 1.25" to 1" reducers. With good flow from the pump I haven't had to add valves to balance the flows.

 

[RemainVayne]

Flexible PVC pipe has very minimal more resistance than hard PVC. A spiral wound tubing has much greater additional resistance than flexible PVC. If you are going with a spiral wound tubing the extra .25" will help a noticeable amount in keeping the flow up.

Flexible tubing is definitely easier to work with than hard PVC and even flexible PVC.

Splitting flow with a Y is pretty easy if you decide to go that route.

Get a 1.25" Y and put it close to the pump. On the 2 outlets from the Y put some 1.25" to 1" reducers. With good flow from the pump I haven't had to add valves to balance the flows.

That's the exact piece I'm looking for, but none of the stores around me carry it. And you're talking about the braided tubing, right?

 

[Oughtsix]

That's the exact piece I'm looking for, but none of the stores around me carry it. And you're talking about the braided tubing, right?

The Y is a mail order item. I have never seen one in a local big box store.

Flexible PVC pipe is much more rigid and much heavier than the braided nylon tubing. It is very hard to collapse flexible PVC pipe by making to tight of a bend unlike poly tubing. A nice trait of flexible PVC pipe is that it is the same OD as hard PVC pipe and can be solvent welded into PVC fittings just like hard PVC pipe.

https://www.pvcfittingsonline.com/pipe/flexible-pvc-pipe.html

I use a lot of braided poly tubing. It isn't very flexible and has a pretty large bend radius. If you try to make a tighter turn with braided poly than it is meant to you will probably introduce a kink to some degree that will restrict water flow to come degree.

Thick wall non-braided poly commonly comes with canister filters. I guess it has it's place but I try to stay away from it.

Pond tubing is nice tubing to work with and I have used it a lot. It has a MUCH tighter bend radius than poly tubing and is much more flexible. The spiral construction provides a pretty smooth interior (not as smooth as poly or pvc) to reduce friction. I really like that pond tubing is black which inhibits algae growth.

I have a used 180g tank that I am in the process of setting up... I am building the stand currently. I have been mapping out the sump, filtration and plumbing in my head. I am HIGHLY considering using PLEX for the majority of the plumbing. I found a place that I have done business with several times before that carries 1" PLEX and a limited amount of push connectors (SharkBite) AT A REASONABLE PRICE! PLEX is more rigid than flexible PVC but does have some bend to it unlike hard PVC. I really like the "SharkBite" type push connectors because they make a very good water tight seal BUT they can be very easily disassembled.

https://www.sprinklerwarehouse.com/Blu-Lock-Tubing-s/11109.htm

Usually PLEX push connectors are incredibly expensive... but these guys carry some at very reasonable prices... ~$3 - ~$4. The only down side it that they carry a limited configuration of different connectors.

 

[Oughtsix]

PLEX is my media server. PEX is the poly pipe.

 

[Tarsun]

i thought as the diameter of a hose or pipe increases incrementally, the flow rate increases asymptotically.

1" pipe flows "X" amount
1.24" pipe flows almost twice as much even though its only a 1/4" bigger...

https://www.hy-techroofdrains.com/water-flow-through-a-pipe/

with that being said though, eheim filter have a much bigger intake pipe thant the outlet pipe. (atleast in the classic filters)

 

[Oughtsix]

i thought as the diameter of a hose or pipe increases incrementally, the flow rate increases asymptotically.

1" pipe flows "X" amount
1.24" pipe flows almost twice as much even though its only a 1/4" bigger...

https://www.hy-techroofdrains.com/water-flow-through-a-pipe/

with that being said though, eheim filter have a much bigger intake pipe thant the outlet pipe. (atleast in the classic filters)

Area = Pi x (Radius)^2

So yes, flow increases at some exponential rate of the pipe diameter. The limiting factor is the smallest diameter pipe in the circuit... which is his 1" returns. But running a bigger pipe up to the returns will reduce the internal friction of the pipe up to the return.