Questions re the Calfo Manifold

[bc_slc]

So I have been looking for the answer to my water flow problems, tossing around the idea of sea swirls vs a wave box of some sort vs tunzees and I came across the calfo manifold last week. I hate the look of powerheads, and their cords and the maintenance and so on and so on. I also think having to hide a box in the rockwork would be challenging. In the future I may opt for a closed loop, but for now, I am looking for something discrete like the sea swirls or the manifold you described.

Background. The tank is a acrylic, custom 60"Lx22"Wx30"T, single center overflow with a 1.5" drain and 1" return inside the overflow. The tank has about a 4" eurobrace that serves as the top of the tank with an entirely open top (no crossing braces of acrylic). The canopy sits such that it covers only about the top 1" of the tank, but does not extend much below that. I run a Mag 12 for the return (my sump is a converted 55gal glass aquarium which is not drilled to run an external pump) plumbed up with 1" pvc, through the bulkhead and then 1" flexible spa tubing comes up the overflow, connects to a 1" PVC "T" and then is downsized to two 3/4" bulkheads through the overflow and runs into 3/4" lureloc.

My plan is run 1" rigid pvc up from the bulkhead, "T" just above the eurobracing, run the PVC on top of the interior rim of the eurobracing around in a complete manifold circle.

Questions
1) Where and to what size should i downsize the diameter of the pipe and T's. Should I run the manifold in 3/4" pipe and then downsize after each output to 1/2"? Or should I run the manifold in 1" and then downsize at the outputs from 1, to 3/4 to 1/2"?

2) I am guessing my current Mag 12 pump is not going to be enough circulation. Is there any way to guestimate how many GPH at 0 head I will need to get about 200gph out of about 8 outputs in the manifold about 6 feet up? I am guessing my 1.5" drain will be adequate, though I may need to remove some of the teeth from my overflow to support a bigger pump.

3) Is there anyway to encorporate alternating flow for more random flow? i.e. I have a 1/2" sea swirl that I could include in the manifold (any advice on how would be appreciated), or I could use a SCWD? I would assume with a SCWD that I would need to close off the circle and make it two separate circuits. I like this idea less as it seems it would stress the pump as it alternates and only provide flow half the time. If it makes any difference, I intend on ballvalving each of the exits before the locline....that may help with including a sea swirl.

Sorry for so many questions, any help would be appreciated.

Mat

 

[Anthony Calfo]

It is a very common mistake to use effluents that are too large. 3/4" and 1" need enormous water pumps! And are truly not needed in most cases.

1/2" (farthest) to 3/4" (nearest to tapped feed tee) tees are more than enough for tanks under... say, 200 gall.s

On the lowest end, you'll want 300-500 gph per tee... higher would be better if favoring 3/4" or larger. Add up desired number of tees and multiply it out against the pump capacity against resistance.

FWIW... I'm using a 5500gph pump on 10 tees for a 120 gall tank

for more threads/info/perspective:

http://reefcentral.com/forums/showthread.php?s=&threadid=520145

 

[ktani]

Hi Mat,

have you considered instead of changing the flow from the sump and using a manfold to have the returns enter the tank via sea swirl? Then use a closed loop for the manifold?

My only concern with further reducing the diameter of the pipe is that you are a increasing friction loss and also increasing velocity of the water. We want good flow, but velocity kills. If possible, I would suggest using the largest diameter pipe possible for the pump you are planning to use. One thing I did ask was using a prefilter for the clsoed loop and he suggested against it as the goal is to put detritus into suspension for the skimmer to pick up.

There are several ways to get around the flow issue through the overflow. One simple one being drilling another hole and putting in a bulkhead.

If you use a sea swirl or two for the returns on the main sump and then a closed loop, the motion of the sea swirls should create some random motion for you. I have seen and like the SCWD, but am very concerned about how much flow you are losing through it. It seems to me that a manifold with some sea swirls would be quite nice and also tidy.

Have fun on the project.

Kip

Anthony's manifold system is truly a wonderful invention. It is so because all you need to do to reduce the amount of entry points is to cap an exit. Thus you can adjust the flow within the tank as items grow and things change.

 

[ktani]

Anthony, on the manifold, with the 10 outlets, what are the sizes you are using? I was curious if there was too much velocity.

Perhaps it would be a great solution on the new tank, but still probably need more than one.

Kip

 

[Anthony Calfo]

very good point Kip... we mention the reduction (to 1/2 or 3/4") at the effluents ... but not necessarily the manifold loop itself and/or coming off the tee. In such cases larger pipe is better to reduce friction/loss.

for my 120 (have done this on two loops for my 240 gall prop tank)... the plan is 1/2" effluents on the front of the tank (farthest from the feed line/tee) and 3/4" around the back and short sides. In both the 240 gall and (eventually the 120), the advantage is the squat nature of these tanks (versus a narrow common 55 gall, eg) where it is very easy to diffuse the effluents over a wider footprint. Thus, we still enjoy high flow... but it is diffused and turbulent (when they converge)

 

[MikeS]

Just a quick thought....if you are going to use two different diameters of pipe, would it not make more sense to have the smaller diameter pipe closer to the pump, and the larger dimeter pipe farther from the pump, in order to keep the pressure up so more water volume reaches the areas of the manifold farthest from the pump?

MikeS

 

[bc_slc]

so it sounds like you recommend that the "effluents" near the input to the manifold (i.e. the back of the tank) be larger size than the effluents at the front of the tank? I didn't see that in any of the linked threads on RC. Any particular reason why?

So to have my math right, if I want 8-10 outputs at 1/2" each at 300-500 gph each then I am looking at about 2400-5000gph. So it sounds like the most reasonable thing is a closed loop.

 

[bc_slc]

So after much thinking about it today, I think I can plumb the closed loop throught the overflow box. This will allow me to not have to drain the tank, and I can maybe use two bulkheads already in the overflow box.

I will end up keeping my Mag 12 return pump and tie in two 1/2" sea swirls.

Then plumb an external pump in a closed loop between the manifold and the overflow box (which already has two bulkheads in it where my sump returns currently are). With the sea swirls on the ends, I think I can get a way with a few less outlets, plugging the caps for those on the short sides where the sea swirls will be.

So questions:
1) Out of curiosity, if the outlets on the manifold are 1/2" would it be possible to include a sea swirl or two in the manifold? I saw lots of questions regarding increasing random flow in the manifold (i.e. OM device, SQWD, wave timers etc) and this could be a very reasonable way to further randomize the flow within the manifold. The resistance should be similar to a normal 1/2" outlet.

2) What is the best way to upsize a bulkhead. My overflow box has two outlets on the side of the acrylic rectangle just below the overflow teeth. They are currently 3/4". If I place a 90" or 45" elbow down (maybe with a slight extension piece of pvc) from the bulkhead and then strainer the end they are unlikely to suck air from the surface. So...how do I make them bigger? Redrill them larger or add a third bulkhead and connect them all before upsizing and then running to the pump?

 

[bc_slc]

So the overflow will have a 1.5" durso drain, a 1" spaflex return with will run to the sea swirls, and then the PVC for the closed loop inputs via these bulkheads. Will be pretty full. I will have to measure it when I get home to see if it will all fit.

So here is a quick diagram of the overflow with the bulkheads (both sides). Not exact to scale, but close. What is the best way to increase the input to the closed loop? drill a third, upsize the bulkheads or is 3/4" x2 big enough?

 

[ktani]

Hi Mat,

some things that I did was to put the input for the closed loop midway into the tank. My thoughts were if it was too high it could end up sucking air from the surface. Too low and I was concerned about sand getting kicked up and then put into the closed loop.

Nothing wrong in putting the closed loop through the overflows, but if you intend for the water to all go through it, you might create some flooding issues instead. Is there a way for you to drill a bulkhead into it, then do a 90 degree elbow and then either out the back or bottom of the overflow? To me this would be a much better solution than trying to put massive amounts of water through the teeth of the overflow.

Personally I would not want to put the Sea Swirls on a closed loop. By having higher continuous flow from the sump, it should create a more random and chaotic motion than by having it come through the manifold. The 1/2" sea swirls with your flow through the sump should give a very fine flow pattern. I am not sure about the potential loss though due to pipe size.

Do be careful about having too many inputs into the closed loop. It can create a caviatation issue. I will contact our pump expert on this matter and get an opinion.

Sounds fun though.

Kip

 

[bc_slc]

Thanks kip.

I agree with running bulkheads out the side of the overflow and part way down. They will need to be upsized as well, but I hope to be able to get enough input with just the two bulkheads tied together.

How could there be a flooding issue? If the input to the manifold comes via two bulkheads in the overflow box which project into the display, then the water shouldn't need to work through the overflow teeth. Or have I missed something?

Mat

 

[ktani]

ahhhh good question Mat. If the output of the pump is larger than the "teeth" of the overflow can handle, it can drain the sump dry and put all the water into the tank. However, if you are doing it via the bulkheads as you have stated, then there is no issues as the input and output should be fine.

As a side note, I did have a problem with one of my sea hares getting caught in the bulkhead as he got too close and got sucked into it. If possible, you might try and arrange the rockwork to minimize potential damage to your livestock. I have also picked snails off it too.

Please post some pictures as you get it done, it would be fun to see it.

Kip

 

[bc_slc]

well it is going to be stepwise. I have one of the sea swirls and may plumb it in tomorrow. Then the other sea swirl. Then I have to decide on a pump for the closed loop.

 

[Toolio]

Manifold Pics?

HowDEE! So I believe I understand the Calfo Manifold, but cannot seem to find any pics showing the designs. Anyone have one or can draw up a quick schematic? Thanks.

 

[bc_slc]

http://www.advancedaquarist.com/issues/sept2003/short.htm