Plumbing return, T orientation?

[drtrash]

i see alot of mixed flow designs and i'm sure if you did it a certain way ts the best because you dont want to do it over but if you could and you understand fluid flow, would you place T parrelel to sump to divert water to left and rght side of tank or run T perpendicular and send water to lefr (or right depending on what side pump is on) side of tank and right side flow would be straight up. Im not an engineer but i would think you would get loose less ( bad stuff, head,pressure...) if T is perpendicular. Having water hit back of T and send some left or right is too turbulent and not efficient. Granted some valving would be needed with perpendicular orientation at some point to help balance pressure and flow

 

[mcarroll]

You may be overthinking. Are you restricted for some reason on plumbing diameter?

What size are you targeting and what flow rate?

 

[drtrash]

Ya I thought that laying out return line to get the most flow, using 1” line, pump size is ok but should of went bigger. I figure if I don’t get much feedback it’s a coin toss and will go the easiest route and cheapest. Hate to install valves if not needed

 

[ca1ore]

I will tell you from personal experience that orienting the T to be right or left and up means more flow through the 'up' unless you are further restricting the ends with something like locline. In terms of resistance, probably makes very little difference.

 

[Art2249]

try to not reduce the pipe diameter at all. Especially if your pump is not pressure rated. Two 3/4 does not equal 1 1/4!!! I don't even have a nozzle on my return.

 

[drtrash]

Was planning on reducing to 3/4" at end of bulkhead with rfg nozzle

 

[Art2249]

Was planning on reducing to 3/4" at end of bulkhead with rfg nozzle

you will get less flow and your pump will wear out faster. use powerheads inside your tank to move water is best IMO. lots of people use those nozzles to make it appear their water is moving faster, but it's not they are getting less flow overall.

 

[mcarroll]

lots of people use those nozzles

The nozzles increase flow velocity at the expense of GPH.

In 1998 (the era of the closed loop) that was a worthy proposition...velocity is the most useful aspect of flow in a tank, not GPH. For adding velocity, you'd want nozzles...and in a CL you have the GPH to burn.

In 2018, like @Art2249 said, it's better ($$) to use powerheads. Run your return pump as unrestricted as possible to get the most out of it.

Ya I thought that laying out return line to get the most flow, using 1” line, pump size is ok but should of went bigger. I figure if I don’t get much feedback it’s a coin toss and will go the easiest route and cheapest. Hate to install valves if not needed

Why not run a more or less straight pipe up to the tank? Why do you need a Tee or other fittings?

And what tank size and what pump do you have?

 

[Norcalreef]

Agreed with what everyone else is saying. I use cor15 with straight 1 1/4” all the way up, just a 90 on the end. Then use mp40 and 2 mp10 for random flow in the tank. I tried adding random flow nozzle and it did not work at all. Had to turn pump up 30% to get same gph and it to work. But then it was sending waves out of my tank.

 

[drtrash]

I have 2 returns, running a rd 50 pump. Have a mp40 already just wanted to randomize the return flow, velocity not a concern but have never used a rf nozzle but idea is sound

 

[mcarroll]

If you're Tee question was about splitting the return pump, then depending on your exact situation a Wye might be your least-friction/best alternative.

Friction should be more equally divided between the two branches, thus flow should be as well. Otherwise you'll need a valve. Might still if the outlets are unbalanced for some other reason like unequal branch length.

Make the whole thing bilaterally symmetrical to avoid the need for valves and a lot of adjustments.

 

[drtrash]

Maybe possible to get close to center with T, with sump all the way to one side i can do a straight shot to one return so was thinking the T perpindular would be easy but would need valving

 

[Art2249]

Maybe possible to get close to center with T, with sump all the way to one side i can do a straight shot to one return so was thinking the T perpindular would be easy but would need valving

They also make a wye fitting. you can see them in my post above. they only come is schedule 80 (grey) but offer less resistance when splitting.

 

[ca1ore]

you will get less flow and your pump will wear out faster.

As Matt notes, overall GPH is reduced but velocity increased. Unless your pump is an absolute piece of junk, increasing back pressure does not cause a pump to wear out faster (it's an oft perpetuated myth). Back pressure actually can result in less power draw.

 

[drtrash]

Where can i fing a pvc wye?

 

[ca1ore]

In 1998 (the era of the closed loop) that was a worthy proposition...velocity is the most useful aspect of flow in a tank, not GPH. For adding velocity, you'd want nozzles...and in a CL you have the GPH to burn.

Was it that long ago ..... how distressing! Quite correct though. I use a pair of the RFG nozzles on my closed loop, but my return is up and over - no unnecessary restrictions.

 

[Art2249]

Where can i fing a pvc wye?

probably need to order it.

 

[Art2249]

As Matt notes, overall GPH is reduced but velocity increased. Unless your pump is an absolute piece of junk, increasing back pressure does not cause a pump to wear out faster (it's an oft perpetuated myth). Back pressure actually can result in less power draw.

Respectfully disagree here. Your pump will last much longer the less it has to work. Unless your pump is pressure rated you should try and avoid reducing the return. Unless you just can't avoid it.

 

[ca1ore]

Like I said, I imagine it depends a bit on the quality of the pump. I don't doubt that much of the plastic junk sold in the hobby today may break under the higher pressures, which is why I won't use them, but a quality unit like an Iwaki will handle pressure just fine. Mine ran for 20 years against 15' of head pressure. We'll have to disagree.

 

[Art2249]

Like I said, I imagine it depends a bit on the quality of the pump. I don't doubt that much of the plastic junk sold in the hobby today may break under the higher pressures, which is why I won't use them, but a quality unit like an Iwaki will handle pressure just fine. Mine ran for 20 years against 15' of head pressure. We'll have to disagree.

Yes I imagine an Iwaki would do that. Many people are using the dc pumps now, including myself. I have worked with pumps and piping in the nuclear industry for many years. The equations dealing with heat transfer and fluid flow all must account for friction and heat generated by water flowing through pipe. Less diameter equals greater velocity equals more heat. More heat means more work by the pump. You see a lot of bad reviews on DC pumps by people that tried to run an 1 1/4 discharge through a 3/4 return. I think this is probably the main reason DC pumps get a bad rap.