Closed loop SCWD for 55Gal

[pdwire]

First time poster....long time lurker.

I am currently in the process of converting 55gal FoWLR to Reef and had a question on how to increase my circulation. I currently have a 1200 Maxijet PH for flow and another to run the Remora HOB skimmer. I have been told that I need more and should add another PH. I have no sump and don't want to add yet another PH so was considering a closed loop and need some advice.

1) Would a Mag 9.5 on a closed loop with a SCWD be adequate flow?
2) Would I need more than one return? or multiple SCWD's
3) Can I split the return back to the tank from the SCWD so that I spread out the circulation? Would this cause to much backpressure?

Thanx for the help

[Entropy]

He is a great link for just what you need.

http://www.sparklingfloorservice.com...losedloop.html

Welcome to RC by the way!

[pdwire]

Thanx for the web site. I have looked at that setup and even emailed Marc about it. I think I can handle the plumbing but that does not address the adequacy of the flow or splitting the returns off of one SCWD

[Entropy]

The scwd is rated to 1400 GPH and is designed to give you two returns so I don't see a problem doing it. Worst case you could T the ends of the two returns to make it 4 returns. I would say you will be pushing around 700 gph which is more than 10 times an hour (the magic number supposedly).

[striker3636]

This is what my closed loop looks like... I had 3 holes drilled in bottom of tank, and the Loc-Line returns are all hidden inside the rockwork... Each of the return lines are tee'd after they leave the SCWD giving me a total of 4 nozzles which I point up toward the top of the tank... This way, the intake sucks water in through the lower part of my rock work, and I have the nozzles pointing up toward the top part of the tank. Gives me good circulation around my live rock and also improves the top to bottom water movement. My SCWD has now been running close to 5 months on the Mak4 at 1200 GPH without a problem in this configuration.

[pdwire]

striker3636. Thanx! That is exactly what I was planning. I guess it would have helped if I explained it better the first time!

[docklink]

striker3636,
Thanks for the graphic. It gives me some ideas also.
How are you screening your intake? I would have some major concerns about "inhaling" anything that got near it in that position, especially turning 1200gph. (Like pdwire, I'm looking at running an scwd with a mag 9.5 at an estimated 700gph)

[striker3636]

Docklink...
For the intake T I used a threaded strainer on each end of the T. The whole idea of using the T was that if one end ever got blocked it wouldnt shut off the supply to the pump... So far it hasnt happened. It also reduces the suction pressure so I don't have to worry about critters getting sucked in. I have seen my peppermint shrimp crawling over the strainers when the pump was on picking at gunk on the outside of the strainer body, without any problem.
The only thing I havent shown in the picture is I use several ball valves in the lines for both the input and output sides.
Maybe once very six weeks or so I'll notice that the SCWD is only blowing out of one set of nozzles, and not switching back and forth. All I do is shut the intake ball valve for a split second and re-open it while the pump is running, and the extra pressure blast will clear out the SCWD... It's usually a couple of leaves of macro or something that makes it past the strainer... I think its happened twice now in 5 months, but clears immediately with the ball valve thing.
Also, the bottom of my intake T is only about 1" above my sand bed (Southdown) but I havent had any issues with sand getting sucked up and blown around.
I have the Mak4 pump on the same timed circuit as my VHO so my closed loop only runs when the VHO's are lit... Goes back to the idea of calmer seas at night... The main circ. pump runs 24/7 but closed loop only daylight hours, and the SCWD makes a cheap wavemaker device for my system during daylight hours.

[striker3636]

I think I might have a picture at home from when I set it up... I'll look this evening, and if I can find it I'll scan it and post.

[FishFamily]

striker3636.....how fast does the SCWD switch output sides with the 1200gph? I'm setting mine up with a MAG12 and was worried the SCWD might switch to quickly.

[striker3636]

I would guess maybe every 6-8 seconds. I can time it later when I get home and re-post.

[docklink]

Originally posted by striker3636
I think I might have a picture at home from when I set it up... I'll look this evening, and if I can find it I'll scan it and post.

I'ld appreciate if you could. Big thanks

[Tarasco1]

Here's another diagram. For a bigger tank, but may give you ideas.
http://reefsanctuary.com/forums/show...ht=closed+loop

Also, these guys were discussing SCWDs:
http://reefsanctuary.com/forums/show...ht=closed+loop

[Snowbrdr_408]

I'm planning on doing something similar to Striker on my 100L but I'm still deciding where to drill my holes. I was thinking of putting two 3/4" return lines 2" from the bottom of the tank on the back wall. That way I could conceal my pvc/locline under my sand or in the rockwork. I talked with my LFS and they said it would be a bad idea to place the holes low on the backwall because of all the pressure being placed on the bulkhead fittings which could potentially cause a leak. Any suggestions as to where to put my drill holes?

[striker3636]

I timed my SCWD.... Its every 5 seconds on 1200 GPH

[striker3636]

Okay...so I'm having a bit of trouble finding the picture I wanted... This first one at least shows the placement of the holes in the bottom of the tank....

[striker3636]

This one shows all the plumbing hooked up... The GenX pump is under the halide ballast and the SCWD is visible just under the bar of the stand... I havent figured out how to label the photo yet, and the size restriction doesnt lend to good resolution.
I found another picture that would have shown the loc-line and T's in the tank, except for the Southdown sand storm