[Ltspd]

First I need to apologize to Organic in regards to our heated debates in the plumbing world. After a long converstaion with Dolphin I have come to a couple of conclusions, which leads to my apology.

1st, we are both right, just on diffrent pages. Organic is correct in the comments on keeping piping at 1-1/2 as far as possible. He is also correct in the conclusion that the manifold is a poor idea. It is, and Dolphin admitted so on the phone. My assumptions and calculations were based on equalling out area's which is correct, but the head pressure that it creates due to the length of reduced pipe run causes the pump flow to suffer thus canceling out the good. Now, if you take a 1-1/2" pipe and reduce it to a 3/4" pipe then you also loose flow, greater than 40% as I have posted. The idea situation is to have 1-1/2 pipe all the way and never reduce it. For most all of us thats impossible. This also explains why the pumps push so much water but have no pressure capabilty as compared to a Iwaki. So they are good and bad depending on how you look at YOUR need.

Now for my help.

I will soon be adding (2)3/4" seaswirls to my tank. This will be plumbed off of my closed loop which now is ran thru a manifold that breaks this into (4) 3/4" lines. Now what I need to do is run 1-1/2 as far as possible to the lines. Here is my delima, I have the tank in place, there are no closed loop holes drilled, all plumbing is done over the back. Currently all the lines come into the tank and emerge inside the LR sturcture. I want to keep atleast 2 of these lines, the other 2 will be replaced by the sea swirls, or atleast I think.

Because things are tight and I have no room to do much behind the tank I need better suggestions. I can add a 1-1/2 wye in place of the manifold but I am down to 3 lines. This would add the benifit of not having to add any bv's to balance things out, 2 would be occupied by the seaswirls. Now I could, at a cost add a 3rd sea swirl, all 3/4". My concern is that I will lose the flow down low in my tank. I have attached a shot of my tank and the green "x" marks where my outlets are.

What do you think? Sould I spend the money and get the 3rd SS, put 2 next to the overflows and 1 in the center? Or is there a more economical solution?

[Rin]

Can you remove the manifold altogether and run the 1.5" pipe all the way up to the tank. Install your manifold behind the tank and run short pieces of 3/4" pipe to the outlets and seaswirls.

Since space is an issue, I imagine you can't use a bv back there. But you can put flow orifices on the 2 lines that go behind your live rock so you get sufficient flow to the seaswirls. If I knew what the manifold looked like, I might be able to make more suggestions.

Alternatively, you can trash the manifold and make a new one for this application using wyes and tees and what-not.

[organicreefer]

you are the bigger man paul.i would like to a extend an apology of my own,we both probly could have used a few less words in our "argument",and we ALL learned something from it anyway,right

even though im still a little unclear on a few issues i guess getting an exact head pressure calculation is pretty difficult,and good estimates are the best we(i ) can do.

anyway since it sounds like you would like four outlets what i think you should do is......get ready for this one



build a manifold!

youve done it already,just make it out of 1 1/2 and run 1 1/2 out of it as far as you can ,all the way and including the bend going over the rim of the tank,not reducing till you hit the water surface.if you use black abs and have a black background it will look fine even if it sticks in a little. .

[organicreefer]

see the sanitary t in wasted plans???stack and cap em up=instant manifold

[Ltspd]

Rin,
Actually the manifold I have been using for the past 9 months is located right under the tank. It takes the 1-1/2" line and breaks it into (4)3/4" clear lines. Each line up to the point of entry into the tank is equal distance, which is about 2-1/2ft. IMO I have always had very very good flow from these outlets. But, according to Dolphin its losing gph.

Mathmatically its doesnt work in my head. According to them, I should have all 1-1/2 lines on the manifold. Now, if I have a tee and all legs are 1-1/2", and only 1 of those is a input I dont have enough column water to supply the other 3 legs, and unless I have a pump that can provide more pressure and water what happens? To me I am having some difficulty seeing the logic. I would see where you would have less pressure at each output. Please explain that one? Water seeks the path of least resitance.

Organic, I plan on developing a plan and a drawing. I am still unsure of the best way to do this, and I cant say that Dolphin cleared anything up for me, actually added to the confusion. To me I will be shooting myself in the foot by splitting (1) 1-1/2 line into (3) or (4) 1-1/2 lines, then reducing down at the last possible minute.

[organicreefer]

yeah with this hobby its always "personalized" isnt it one of the coolest things about it,exploring each others ideas and expanding on it /modifying it to suit youre particular setup(sometimes budget )

its always best to put it on paperpost youre plans please,alot of us cant get enough of the subject

[Ltspd]

Rin,

Is Boyles Law V1P1=V2P2 the answer?

I am searching for the answer to my question. I may have to dig out the fluid powers book,

[golfish]

Awwwww, I have tears in my eye's

Paul,
I think 2x3/4" SS's is good. The problem I have found is shooting water across the back of the tank where the SS's can't reach. I have my sump return spray bar blowing across the back. I seem to remember you do something similar.

Two SS should do fine on your tank. I have used both the nozzel and Y fittings. I like the nozzel fittings the best. probably because with the Y fitting water is forced up against the overflow .

I still say you should get the 1" SS's

[Rin]

Boyles law describes the general characterists of a gas. That is, as pressure goes up, volume goes down. (vise-versa) Liquids (esp. H20) are incompressible so boyles law does not apply here. You are thinking more like a mass balance equation:

(density1)(area1)(velocity1) = (density2)(area2)(velocity2)

Which basically says that (at constant density) as area increases, velocity decreases. BUT, at constant density, mass flowrate remains unchanged.

So why all the hubbabalu about pipe sizes and where we decide to reduce the pipe? FRICTION

Fluid at the wall of a pipe does not flow. Not at all. Fluid close to the wall of a pipe flows very slowly. Fluid flows fastest at the center of a pipe. This is friction. For very small pipes, this is significant. Laminar flow in a pipe creates more friction than turbulant flow--but don't worry about that. Very few aquariums are capable of creating laminar flow--except for the guys with sumps in their basements.

So this is why you don't want to use small pipes where a larger pipe will also work.

Having said all that. 8' feet of 3/4" pipe isn't going to add that much more friction to a system than 8' of 1.5" pipe. The reduction from a 1.5 to 3/4 is going to add so much friction that the differences due to pipe dia. can be considered inconsenquential for purposes of determining frictional losses in the pipe. (did you catch all that? )

Hope that helps....

[Ltspd]

Ok, while riding my bike inside I have a good 40 minutes or so to ponder the days questions. Well today I was pondering the problem we have been discussing.

First, I need to thank Scuba for the idea, which I have completly overlooked until we were discussing it today on the phone.

* Water seeks its own level. This is simply proven by a water level, which I have used on numerous occasions. If you fill a tube with water and hold both ends up then the water will balance. This is done without ANY mechanical force acting upon it.

* we are discussing a closed loop system. A system that is never exposed to air. A system that if power is shut down the water just stops, it doenst backflow into a sump.

* there is no head pressue on a closed loop system, or atleast none at the point of level balance. This is the water line of the tank.

* the only head pressure we overcome is the part that is above the water line, and the increased friction of the reduction of pipe size.

* the am3000 is only a device that is circulating the water, its only head pressure to overcome is the the above 2 items.

This explains why I have great force and flow coming out of all 4 of my pipes.

Thoughts?

[wastedincome420]

[quote]Originally posted by Ltspd


* there is no head pressue on a closed loop system, or atleast none at the point of level balance. This is the water line of the tank.

* the only head pressure we overcome is the part that is above the water line, and the increased friction of the reduction of pipe size.

* the am3000 is only a device that is circulating the water, its only head pressure to overcome is the the above 2 items.

The top two are the ones that still kinda confuse me. So ANY pipe/fittings below the water line in the tank does NOT?? count as head???
So in my plan the only fittings that will count as head is the elbows going in to the SS on top

[Ltspd]

Rin,
Correct on Boyles law, it applies to gas. I dug out a old fluid powers book from college

Pascals doesnt apply either, its for under compression.

2 comments that apply to this discussion

When the fluid is not moving, it can transmit force, only, without any pressure loss, no matter how restricted the fluid column or pipe may be.

When the fluid starts moving, power is transmitted, and any restrictions in the pipe become significant.

Rin, do you know what the force might be of the am3000? If so we can calculate the psi, thus enabling us the determine the recommended velocity of the pipe and then plugging that into a flow capacity chart.

Are (4) 3/4" lines cumulative forces?

[Ltspd]

wastedincome420,

I am begining to think that the issue may be the flow capacity of the pipe more so than the head pressure........


Why did I get into this question I got so much I should be doing other that this,

I also think I may be just fine by only replacing 2 of the lines with the SS, and not worring so much about the short run of pipe reductions.

[Rin]

Wasted...

Head pressure is the is the vertical column of water that a pump can push. Imagine a really large U tube with a pump at the bottom of the U. When the pump is off, the level of water on each side of the U is equal. When the pump is on water will be higher on the outlet side of the pump. The difference in the volume of water on each side of the U(x force of gravity) is the head pressure.

Things like water density, pipe walls, orifices, tees, elbows, and others contribute conteracting forces. . Collectively these forces are referred to as pressure loss, because these forces reduce the effective head pressure on a pump.

Neat, uh?

[Rin]

Paul,

I don't know what the specs of the AM3000 are. Having a pump curve is crucial to any serious design. Most pump curves are generated through emperical data, almost all manufacturers can provide one. As the pressure losses increase, the performance of the pump changes. Pressure-rated pumps have flatter curves than non-rated pumps.

For determining losses in your connections:

4 3/4" are cummilative, but not additive. Use the equation for resistance in a parallel electrical circuit to determine the resistive force.

1/(total resistive force) = 1/port1 + 1/port2 + 1/port3 + 1/port4

It works the same.

[Ltspd]

Originally posted by golfish

I still say you should get the 1" SS's

Cant, there is not enough room behind the tank. I spoke with Ed at SS for some time on this Monday when I ordered mine.

[Ltspd]

Ok, I can spend another 200 bucks on another SS and some plumbing fittings and I think do some good. Key word is think. I can put a double 1-1/2 wye on the closed, redo the drain side of the closed (I would have to, to make things fit) and redo the sump return and clean it up. I could do 1 project at a time, sump return, then drain, then SS. I would have (3) 3/4" SS on the tank. They would be at the red x's. I would kill all 4 green x's and the unsitely piping that goes along with it. I still might be concered about lower flow, but could handle that by turning them down ward. Now, can I get the 2 outer SS turned so the are rotating 90 deg but not slamming into the overflow boxes. 90 deg would be parellel to the back of the tank then going perpindicular to the front. The middle one would be always pointing frontward. I could also sync them together to produce a "wave" type current.

If I cleaned up the overflow returns I would kill the flex loc's in their current locations and bring them up and over the front of the overflow boxes with some 90's. I could keep it all 1" until it hit a single loc-line that would go to a fan connection pointed sort of horz. I would plug the bulkhead fittings.

It would be a lot of work, but then I love tinkering on the tank, lol.

Or would I be just fine the way I am, adding the (2)SS where I was going to in the begining?

[scubadude]

Originally posted by Ltspd
Ok, I can spend another 200 bucks on another SS ..............
It would be a lot of work, but then I love tinkering on the tank, lol.

Or would I be just fine the way I am, adding the (2)SS where I was going to in the begining?

Sorry we got disconnected yesterday bro! I really think you are on the right track here....well since its your money and not mine I like the idea of 3 SS's and think your above thoughts are really on the right track....I think you would be fine with only 2 SS's but I think you would be getting the most out of the AM3000 if you had 3 of them hooked onto the loop....Ya know its usually true w/anyone that No one knows their setup like the person who designed it and this is especially true with your setup....I would have posted sooner but I had to deal w/my Auto Topoff yesterday and it was a PIA! BTW thanks for referring me to Brian yesterday....He did fix my problem...and w/out any cost! A great guy! But I really think your loop can be accomplished very effeciently w/out any manifold....your sump is definately a different story, however your loop is whats gonna be your main current generator NOT your sump pump...there will be VERY little head in your loop. Man I can really relate to "My head hurts " fire up that bike and just take off MAN! Or else you will be going backwards if you think about it too much!

[Ltspd]

Glad you got the top off working right, Bryan is a great guy. Now you can go on Vacation!!!

I think your right about the tank. I have come so far from when I began 2 years ago. Just imagine the next tank,

[organicreefer]

i kninda like youre plan of two seaswirls and two outlets myself.....im just worried you might have alot of head for that many????

any way ,amybe three ss's if you can mount one (atleast) on the front of the tank somehow(like scubas)pointing to the back.the flow from the fornt would alternatley hit the ones coming from the back,making a nice randome turbulent flow...just a thought