Manifolds & Flow rate dynamics & AM3000

[Ironreef]

This is what makes the pump good= 1 1/2 pipe get alot of flow . If thats to much for your needs be creative and restrict it a little ,back it off but it still will be better than most pumps= cheap to run,quiet and later if you need more spend a few $0.01 and redue the plumbing

[Rin]

Finally, I've read to the end of this thread. *whew*

I may have missed a couple of things through all the friendly bantering. But I think the basic question is how come we get less head pressure through these manifolds of smaller pipes.

First, to sort of answer Organicreefer's question about flow--here is the approximation that I use:

The change in pipe dia is equal to the change in volumetric flow squared (assuming linear velocity is unchanged). Paul hit on it when he talked about the AREA of a pipe rather than it's diameter.

When calculating head pressure on a manifold. Each port is calculated separately. That is, head pressure from the pump would be equal at all ports if the manifold were horizontal. Vertical manifolds start with the pressure losses at the level of the port--this is why you need an even number of ports--it really helps with balancing the system.

Total approx head pressure can be calculated by the following:

1/total= 1/port 1 + 1/port2 + 1/port3 + etc....

BTW, too little head pressure can be just as bad as too much. The best thing to do is to get a pump curve (from the manufacturer) for the pump and design your system around the pump curve.

[BigLar]

It would be nice if Dolphin would give us designs of the "best" way to plumb this pump in a closed-loop!

[Ltspd]

Dolphin sells a manifold that attaches to the pump itself, that if one looked at it, you could logically assume that it were intended for a manifold.

Here again, Area plays into the equation.

[organicreefer]

big lar ,have you read dolphins plumbing page?its all right there use 1.5 inch pipes,don not reduce below one inch ,reduce at the last possible point= the best way

[golfish]

use 1.5 inch pipes,don not reduce below one inch ,reduce at the last possible point= the best way

Kind of conflicting isn't it? Why do they sell 3/4" manifolds that attach to the pumps output?

[wastedincome420]

Thats what I said
But the quote that organic posted from dolphin is ALL TRUE. It's "Dolphins" reply to "my" e-mail to them;)
I dont get it either

[golfish]

So this leads me to think that Dolphin should stick to building pumps and let the pros figure out the plumbing

[Ltspd]

Guys, please refer to AREA.

If you go from 1-1/2 to 1" and thats it then you lose 44%.

Area of 1-1/2 pipe = 1.767 sq in

Area of 1" pipe = .78 sq in

Take .78 / 1.767 and multiply by 100 and you get 44.3%


This is what I have been saying since the first thread, but it seems to be ignored.

[wastedincome420]

That CAN be very TRUE
I mean (I dont have one YET) EVERY one I know that use a am3000 says that they are very powerful, and whos going plumb it in ONE 1 1/2" return ??You have to split for something right???
AHHHHH I dont know!?!?!?!??!?

[Ltspd]

Guys, I have a am3000 plumbed with 1-1/2 pipe to my manifold that breaks it into (4)3/4" lines. I can stick my hand in front of any of those lines inside the tank and feel the pressure.



My AREA"s equall out.

[organicreefer]

ltspd,im sure you get decnt flow out of youre manifold,but an ampmaster capable of more than you give it credit for,after all ,you dont have the other way in front of you to compare;)
did you guys read the emails from dolphin?????dont you think they have tested their pumps????i thought this was long over with ,some people just dont want to hear certain things i guess....im done with this subject........

[organicreefer]

one last thing the reason they sell a manifold with 3/4 inch outlets is because alot/most of people with existing setups pretty much have 3/4 plumbing.it also applies to alot of skimmers etc.
its a simple way to multi task an ampmaster to an existing set-up....not the best way.

[golfish]

Guys, I have a am3000 plumbed with 1-1/2 pipe to my manifold that breaks it into (4)3/4" lines. I can stick my hand in front of any of those lines inside the tank and feel the pressure.

Paul,
I got it. I'm just not sure if Dolphin does Now, I know what their referring to, its just that they should make themselfs a little more clear.....

Oh yeah, I'm still not sure I agree with you I do know that I reduce down to 1" at a 1.5" tee and get more then enough flow from my two 1" Sea Swirls............that's really all that matters to me

[organicreefer]

Originally posted by organicreefer
directly from dolphin:

You will not loose pressure at the manifold, however when you enter the 3/4" plumbing your head pressure will increase quite a bit. For example, when plumbing a 180 with 2-3/4" returns + a seperate skimmer, the best way to plumb from the outlet of the pump is to use 1.5" out of the pump all the way to the return bulkheads & then reduce to 3/4" with a reducing bushing. As for the skimmer, tie into yout 1.5" line with a tee & a Ball valve to requlate flow & also reduce at the skimmer inlet. By plumbing this way your flow rates will be at least 25% higher than if you used a manifold & 3/4" plumbing to go to the return lines.

also from dolphin:

The people saying to run 1.5" to each sea swirl & spray bar are correct. This is
the way to get THE most flow, even though some people have plumbed other ways
(manifold) and it works for them personally. They are wasting a good portion of
what an Amp Master 3000 can produce in the way of MAXIMUM flow rates.
Tom Briscall Jr
VP Dolphin Aquarium
850-434-9880

[scubadude]

Check this out for calculations on friction loss...excellent point....And I think paul has done his math on this area....I think we all agree that we are gonna lose some by reduction ....but if there is an effecient way to do multiple outlets off of a AM3000 its with a manifold with the correct calculations in place....heres the link to figure your Friction Loss

http://www.plumbingsupply.com/flowchart.html

[Rin]

Actually, the friction losses are why you want to do what Dolphin (And Organicreefer) are recommending. If you use a 1.5" manifold with four 3/4" ports, you loose a lot more pressure due to friction losses than you would if you had four 1.5" ports with 3/4" reducers at the point of service. For the mechanically challenged, loss of pressure = loss of flowrate.

It took me a while to figure out what exactly Organicreefer was so upset about. And I think I got it now.

Some folks, I think, are trying to figure out the best way to plumb the pump for max flow through a manifold--while the rest of us are trying to explain the math without really answering the question.

I went to school for 5 years to learn the math behind this very issue. The short answer is that eveybody's system is different. The dynamics behind transporting fluids is extremely complex. You can have a perfect system and then decide to add just one more line, elbow, or tee--BOOM--it's all f----d up.

Here are some rules of thumb on installing plumbing:

1) Always use a pump that is slightly overrated for your application. If you need 1200 gph--go to 1500 gph. Add your services together then multiply times 1.2. This will cover your basic needs. Those who have extensive plumbing systems (sumps in the basement and the display tank on the 3rd floor) are going to need to use all those head pressure calculators to ensure that the pump can do the duty.

2) When limiting flow always regulate the output from a pump. Never starve a pump.

3) if you have to cut back flow severely. (less than 20% of the pumps total rating) install a local recycle line just for the pump. A recycle line is a type of closed loop. Tee off a line from the outlet and pipe it to a tee in front of the inlet. Be sure to valve it so you can regulate the recycle. A properly sized system should never have to use this. If you do use a recycle line, reduce it to a 3/4" or 1/2" pipe.

3) Pay attention to head pressure. Pump curves are handy for this. There is a sweet spot on all pumps that will maximize flow. Aim for the sweet spot.

4) larger pipes have less frictional losses. Always use the largest pipe available...if your pump has 1.5" outlet, use 1.5" pipes and use reducers at the points of service. The other side of this coin is that you always want a pipe to be full. If a 1.5" pipe doesn't stay full for your application, go to a smaller pipe. This reduces frictional losses due to something called plug flow. It is also less noisy.

5) If you don't have room to install a ball valve (for the purpose of regulating flow) use an oriface. Like hard-currancy ladies, they're cheap and easy, but you don't want to overdo it.

6) Hard pipe where possible, flex where necessary. Remember to install a small piece of flex pipe somewhere between the pump and point of service (tank, sump, skimmer). This will reduce noise and stress. Not installing a flex is a good way to crack a glass tank.

7) When installing valves, make sure they are line-size. There isn't much use in putting a 1" valve on a 1.5" pipe. It just increases your pressure losses.

8) Manifolds are great. Balancing them are a pain in the butt. Remember, pressure is equal at all ports on a manifold. Decide on which port can take the most variance on flow (usually the display tank return) and tune that line last or not a all. If you can't get sufficient flow to one or more of your services no matter what you do, then your pump is undersized for your application or you have too many things in your piping that is adding to the pressure losses.

Everything in the plumbing adds to pressure loss--elbows, orifices, joints, valves, bends, tees, instruments, etc. Even the material of contruction makes a big difference. Those generic head loss tables assume straight pipe. Always add some extra for every item in the pipe. There are tables that give the losses for different items--if you can find them.

For what it's worth, there it is.:eek3: Good luck.