View Full Version : CL to summarize and questions
07/18/2005, 06:55 PM
Ok Anthony i have read through most of the Manifold sticky. But i have a few specific questions.
Before i start i just want to give my stats.
120 AGA dual overflow
40 Br sump/fuge/MR-2 Skimmer
CL would be over the top method
To summarize what i have read
1. The best number of nozzles is 10 per gallon with some extras capped off.
2. largest diameter PCV pipe allows for more flow ( Poussiles Law)
:D :D :D :D
1. Would a pressure pump be better on a CL manifold (many small 3/4 lockline openings) as opposed to a circ high flow pump all taking watts into account.
2. Can the manifold just go around the back and two sides of the tank, leaving the display panel free and open.
3. Would the CL pump be better mounted on the ground of the tank (ie. 5 + feet to water surface) or build a stand for the CL pump to sit at the level of the Bare Bottom tank (ie. elevated off the floor).
4. Which do you recommend the manifold style or a static 2-4 outputs on the back of the tank.
5. How do you accuratly measure head loss with the RC pump calculator.
Thank you very much, i know i have a lot of questions.
07/18/2005, 07:47 PM
to give a bit if an updated summary of my own:
- I believe the best way to drive a manifold is via a pump that is separate from the sump loop and tank overflow.
The reason is that the size of pump usually needed to handle most of the display water flow needs (and elliminate the need for powerheads or other water moving devices) is so large that it will be too turbulent and/or noisy. [This is the common problem that aquarists have had for years with appropriately large sized water pumps, but undersized overflows and/or undersized sump sizes. It causes too much action/turbulence in the sump and can lead to the aspiration of air (microbubbles in the display) and dreadful noise (sump and topside overflow)
- sump loops (especially with under-drilled so-called reef-ready displays) are best executed with a modest amount of water flow on a quiet loop from overflow to sump and back up to display. Something around 800-1000 gph does the trick (like a quiet one or mag 9 pump at 4' head) on typical home sized aquaria. This way you can enjoy downstream skimmers, refugiums, carbon & heaters, etc hidden in the sump without the sound of a toilet flushing in an overdriven overflow from above :D
- Keep your manifold pump and sump loop pump separate.
- then... the majority of display flow needs can be handled on a closed loop (manifold harnessed or otherwise) via a single hole used to feed (flood actually) the CL pump.
- for max flow/min noise and reduced risk of cavitation... keep the closed loop pump as close to the feed/flood hole in the display with minimal pipe length run and minimal turns (used soft elbows when necessary) and use pipe at least as large as the pump calls for (increased can be better for increased flow)
- mounting the CL pump at or above tank level gives you an advantage (less head loss)
- drill the hole for the CL pump low enough in the tank so that it does not create a siphon/suction of air form the surface... yet drill no lower than you have to in case of bulkhead leak/failure (not draiaing all the tank then). I suggest drilling the feed/flood hole for the CL pump around 1/4 to 1/3 from the top of the tank
- use larger pipe too on the output of the CL pump up to and around the manifold... and only reduce as needed at the tees for effluents. For example: ~ 5000 gph water pump on a 120 gallon display with a 2"bulkhead feeding the pump and 1.5-2" pipe coming off the pump and running the loop for the manifold. Off the manifold 15 tees (three capped to give 12 running effluents for a 1 tee per ten gall ballpark/guide) come off the loop on reduction to say 3/4" (open nozzles) or 1" (flared nozzles)
- running a complete loop of pipe has its advantages (friction/loss of flow) over dead ended bars/tees for a manifold
- neither the feed for the manifold nor the return from the sump need to be through drilled holes in the tank. There is no advantage beyond aesthetics. But it does at least slightly reduce strength/integrity of the tank for drilling the extra holes. My advice is that if you don't need the extra holes... don't drill them. You can simply return water over the top of the tank.
07/18/2005, 07:56 PM
bond007069... now for the specific answers to your questions :p
1) do consult your pump mfg on this one... I'm not that good on physics here. And I suspect that a properly mounted (no excess restrictions/friction or head) and conservatively oversized pump will make this question/concern moot.
2) a complete loop would be better... you'll get more flow for it.
3) yes... do get that pump as high as possible to reduce head/loss
4) if not the manifold, then something else that creates random turbulent water flow from multiple points. Having only 2-4 effluents for a 120 gall tank here sounds like dreadful idea. I am sure you will have dead spots/areas in the tank if you go this route... possibly long term problems (nutrient accumulation)
5) do not obsess over this my friend... you need to overestimate your total flow needs as it is to account for the pump aging/tiring in time, clogging, friction, etc. Your 120 gallon tank needs at least 30-50X turnover if its to be a reef tank... lean higher if the tank is for growing stony corals. A CL pump that gives 4-5K gph will drive around a dozen 3/4" tees on a tidy and well-plumbed manifold. This will give you many points to finesse water flow and dead spots in the tank... and it will free you of the burden of powerheads or expensive water motion devices
07/18/2005, 08:39 PM
thank you Anthony, those were excellent answers :D
07/18/2005, 09:00 PM
very welcome my friend :)
07/19/2005, 09:38 AM
Anthony, are you using the Hammerhead Seq?
Whats your in/out diameter PVC.
Do you think that is too large a pump for a 120 g.
Would a Dart, suffice? for a reef possibly even two Darts, but then we have about the same watts with a little extra cash up front.
07/19/2005, 10:57 AM
I am using a Hammerhead on about a dozen 3/4" effluent tees coming off of a 1" manifold. I chose the 1" for a little extra working room... but frankly wish I had gone 1.5" (or even 2") for better flow. And nope... its not too much flow at all for the tank which has mostly LPS corals in it. The feed for my pump is 1.5" pipe and I run 1.5" pipe off the pump until it meets the (1") manifold.
07/19/2005, 11:56 AM
Thank you very much
07/31/2005, 11:26 AM
I was womdering if this picture would help get my point across.
Above you said " if not the manifold, then something else that creates random turbulent water flow from multiple points. Having only 2-4 effluents for a 120 gall tank here sounds like dreadful idea. I am sure you will have dead spots/areas in the tank if you go this route... possibly long term problems (nutrient accumulation)"
Dues to lighting canopy and other asthetic reasons i am opting for a different set up.
I would still like to use 1.5 inch PVC and the Dart but this would be directed down the back corners of the tank. This set up is does not make a complete circle.
I also figured that the corals would like a cross wise current, instead of a down on top of them. Maybe more natural, i dono it is a stretch.
Ok so i hope you can understand the pic.
07/31/2005, 11:53 AM
I really don't follow your point about "crosswise" current, mate.
At any rate... we are not trying to create laminar flow of any kind - from above or the side.
But rather, turbulent flow by the convergence of multiple effluents.
Turbulence cannot be created with less, larger outlets (you get something more akin to laminar currents instead) - hence my rec's for manifolds or the like.
If you can tolerate the aesthetic eyesore (to me) of running or hiding vertical pipes... then, that's okey-doeky to me :p
Do whatever it takes to create turbulence.
You might look at the link I just posted near the top of the CL manifold sticky in this forum. It mentioned a spider manifold that takes a 1.5" feed and gives eight ports. Maybe you can do something creative with that? Perhaps even along the lines of these vertical discharges?
09/13/2006, 11:54 AM
I have an oceanic 175 bow front. To do a CLM the sequence 4200sw, that I was going to get, seems too small following this thread. But I do not see the size tank that you are using the hammerhead on. Marine depot carries the sequence sw pumps, which of all these would be my best choice.
09/15/2006, 08:04 PM
I have a hammerhead on a CL with a manifold. All 1.5" plumbing. Ten 3/4" outlets, two with valves so they can be closed. On a 30" tall tank, even with all ten outlets open, I get descent flow at the bottom of the tank. Whirlpool? No. But good. Make sure to keep your sequence well ventilated or it can heat your water.
09/16/2006, 07:30 PM
Thanks for the response!
09/17/2006, 04:14 AM
Please post link to sticky for CL
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