Return Line Design

[roberthu526]

Hi everyone.

I am in the process of setting up a 125G system and I am not sure if the return line I am thinking of will work. Can someone please chime in and see if there is any potential issues with the design?

The idea is to have water coming out of return pump and into a 1.25" pipe which will be Tee'd off at the bottom of the tank into one 0.75" return nozzle and one 1.25" pipe. The 1.25" pipe will then direct the water to the other end of the tank and go up to a 0.75" nozzle.

Below is a rough drawing I made to show the idea. Any inputs are much appreciated!

 

[mcarroll]

Sounds fine. What pump and flow rate are you thinking of?

 

[saltyfilmfolks]

The only nit picky thing I see is the return on the right will have more pressure as it's closer to the pump.

If you put the T centrally it'll even out the flow between the two.

Balancing the flow with uneven sized pipe has never worked well for me.

 

[Ryan Browne]

If you want the flow to be evenly distributed between both return nozzles you will most likely need need to put a valve on the one closest to the pump. If you have a good
pump, you could build a 'manifold' type return, and have two or more returns. Manifolds are typically used to send flow to multiple reactors so that only one pump is used. The picture below is from a bulk reef supply tank build. They used one pump, (On the right). The single pump is used for both the returns and as a manifold to power reactors, but you need a good pump to do this. Hope this helps.

 

[Grey Guy]

They sure are pretty when they are new.

 

[roberthu526]

Sounds fine. What pump and flow rate are you thinking of?

I have two RODC 10500 sitting around and also a Waveline 12000. These all have 1.25" threads at the output so I figured if one fails I have two backups. I am shooting for 500 - 800 GPH for the returns.

 

[roberthu526]

The only nit picky thing I see is the return on the right will have more pressure as it's closer to the pump.

If you put the T centrally it'll even out the flow between the two.

Balancing the flow with uneven sized pipe has never worked well for me.

That's exactly what I am worried about. I really want to have the two nozzles have similar flow rate. I may have to re-position the sump to make that happen.
Thank you for your input!

 

[Ryan Browne]

I saw this on reefbuilders a while back. 1 pump, two returns. Even flow to both nozzles, not sure if its out yet.
https://reefbuilders.com/2017/08/16/maxspect-turbine-duo/#

 

[roberthu526]

If you want the flow to be evenly distributed between both return nozzles you will most likely need need to put a valve on the one closest to the pump. If you have a good
pump, you could build a 'manifold' type return, and have two or more returns. Manifolds are typically used to send flow to multiple reactors so that only one pump is used. The picture below is from a bulk reef supply tank build. They used one pump, (On the right). The single pump is used for both the returns and as a manifold to power reactors, but you need a good pump to do this. Hope this helps.

Thank you for the reply!
I don't really want to put a valve to restrict the flow for two reasons:
1. It is not very energy efficient and it may create heat that is not necessary;
2. I am going to use a DC pump to control the flow anyway.

I have thought about making a manifold but I worry with the reactors hooked up to the return line I will need to adjust the overflow every time I add something or take something off the manifold. I have read this on gmacreef's reef tank plumbing guide. It is tempting but there are certainly drawbacks.

 

[roberthu526]

I saw this on reefbuilders a while back. 1 pump, two returns. Even flow to both nozzles, not sure if its out yet.
https://reefbuilders.com/2017/08/16/maxspect-turbine-duo/#

BOY this thing sure is sweet!

 

[saltyfilmfolks]

That's exactly what I am worried about. I really want to have the two nozzles have similar flow rate. I may have to re-position the sump to make that happen.
Thank you for your input!

PVC 45 s and a t is a simple manifold.

 

[Ryan Browne]

I don't like to use valves or Tee's on my return. Let your pump run free. In the old days, people would use valves because there wasn't an easy way to control
the flow of a high power pump. DC pumps solved that problem.

I like the section on gmacreef's webpage "Should I install multiple return lines?"

http://gmacreef.com/return-line-plumbing-reef-aquarium-sump/

Thank you for the reply!
I don't really want to put a valve to restrict the flow for two reasons:
1. It is not very energy efficient and it may create heat that is not necessary;
2. I am going to use a DC pump to control the flow anyway.

I have thought about making a manifold but I worry with the reactors hooked up to the return line I will need to adjust the overflow every time I add something or take something off the manifold. I have read this on gmacreef's reef tank plumbing guide. It is tempting but there are certainly drawbacks.

 

[saltyfilmfolks]

I don't like to use valves or Tee's on my return. Let your pump run free. In the old days, people would use valves because there wasn't an easy way to control
the flow of a high power pump. DC pumps solved that problem.

I like the section on gmacreef's webpage "Should I install multiple return lines?"

http://gmacreef.com/return-line-plumbing-reef-aquarium-sump/

They also used valves because the pump runs more efficiently with back Pressure.

 

[mcarroll]

Keeping the return simple is better than just about anything else.

Pump
Simplicity is one of the main reasons AC pumps make so much sense on a return.

You already have DC pumps around, so different story...use 'em.

But if you had any other use for the DC pumps or thought they had significant re-sale value, I'd heartily suggest getting a plain, right-sized AC pump for this application. Eheim, Quiet One, Sicce, Mag...lots of great options.

Plumbing
I would set your plumbing up how it makes the most sense to you.

Assuming you still like the diagram you posted, I'd probably do it almost without modification to see how it works.

You will want 1-2 valves to balance the outputs IF you require them to be equal or to otherwise have control over the flow from each outlet for some reason, but...

Remember:

• Flow to the two returns in your plan do not have to be equal. That's not a rule.
• You don't really need more than one return.
• You need all of the flow to go into the tank. That's the only rule. ;Drowning
• Tank flow is via powerheads, not the return pump.
• The job here is just delivering sump water to the display in a timely and hopefully unobtrusive manner.
• We might debate whether 2X, 5X or 10X is "timely", but under normal circumstances there's no need to complicate the return beyond that.

 

[roberthu526]

I don't like to use valves or Tee's on my return. Let your pump run free. In the old days, people would use valves because there wasn't an easy way to control
the flow of a high power pump. DC pumps solved that problem.

I like the section on gmacreef's webpage "Should I install multiple return lines?"

http://gmacreef.com/return-line-plumbing-reef-aquarium-sump/

Yep that's the plan!

 

[roberthu526]

They also used valves because the pump runs more efficiently with back Pressure.

Really? Back pressure makes the pump more efficient? I have never heard of that.

 

[roberthu526]

Keeping the return simple is better than just about anything else.

Pump
Simplicity is one of the main reasons AC pumps make so much sense on a return.

You already have DC pumps around, so different story...use 'em.

But if you had any other use for the DC pumps or thought they had significant re-sale value, I'd heartily suggest getting a plain, right-sized AC pump for this application. Eheim, Quiet One, Sicce, Mag...lots of great options.

Plumbing
I would set your plumbing up how it makes the most sense to you.

Assuming you still like the diagram you posted, I'd probably do it almost without modification to see how it works.

You will want 1-2 valves to balance the outputs IF you require them to be equal or to otherwise have control over the flow from each outlet for some reason, but...

Remember:

• Flow to the two returns in your plan do not have to be equal. That's not a rule.
• You don't really need more than one return.
• You need all of the flow to go into the tank. That's the only rule. ;Drowning
• Tank flow is via powerheads, not the return pump.
• The job here is just delivering sump water to the display in a timely and hopefully unobtrusive manner.
• We might debate whether 2X, 5X or 10X is "timely", but under normal circumstances there's no need to complicate the return beyond that.

I totally get what you are saying but I am a little OCD. I want the tank symmetry by having the overflow in the center. I know it is not necessary but I can't help it...

 

[saltyfilmfolks]

Really? Back pressure makes the pump more efficient? I have never heard of that.

http://www.cyclestopvalves.com/geninfo_2.html

 

[roberthu526]

http://www.cyclestopvalves.com/geninfo_2.html

Wow learned something new! Thank you for sharing!

However I did notice the article stated that it is okay for cool water as restricting flow can cause additional heat. I wonder if this is going to harm the pump and shorten the life span.

 

[saltyfilmfolks]

Wow learned something new! Thank you for sharing!

However I did notice the article stated that it is okay for cool water as restricting flow can cause additional heat. I wonder if this is going to harm the pump and shorten the life span.

Yup. Always learning. I wanted fish and now I'm an engineer. Lol.

I assume a good brand works to our temps and salt specs.