Sleek concepts?

[dpg]

I have a 84x24x26 peninsula style tank being commissioned and need to know how to place the 1" returns in such a way that it looks sleek - the returns will be coming from one of the short end panels (where the overflow box is) and span the length of the tank. I want to utilize the flow provided by the returns but dont want the returns on top of the eurobrace.

A great suggestion from BWA was to groove the underside of the eurobrace for the returns but the tankbuilder is unable to do that .. any concepts or done-did-thats?

[mark]

can't go under the brace, you don't want to go on top of it...tough one

[parkinsn]

Are you willing to drill the bottom and risk the use of check valves?

[shrimpchips]

Are you willing to drill the bottom and risk the use of check valves?

Why not just run a dedicated closed loop, and avoid any potential tank-draining events?

[mseepman]

Your tank almost mirrors the one I'm picking up in a couple of weeks from a builder in Calgary.

Is there any reason you don't want the returns to go on top of the Eurobrace? Are you not planning on any canopy? If that's the case, I understand your issue.

[parkinsn]

Why not just run a dedicated closed loop, and avoid any potential tank-draining events?

Because then he would still have to deal with the return.

Why not just put it on the end that will be on the wall/overflow side and suppliment the flow with power heads or CL?

[dpg]

Appreciate the inputs.

CL's and PHeads were options I considered but still want to utilize the return flow, and minimize costs associated with a CL.

I was considering this, http://www.reefcentral.com/forums/showthread.php?t=1502129&page=12, any thoughts?

mseepman, I'm curious as to how your planning out your peninsula style tank?

[Funky_Fish14]

You can still drill lines into the bottom on the far end (opposit the overflow) without risking the use of check valves.

How do you get away with this?

- From the underside where the return goes in, as you go back toward the overflow, you bring the 'return line' back upward to above the waterline in the aquarium. (do this with any associated lines run in such a way). From a point above the waterline, drill a small hole in the line, and have a hose running spraying a small amount of water into the overflow box. (this water comes from the return line). What this does is that in the event of a power outage, etc... the pump shuts off... all the lines 'start' to drain, (because of a syphon effect), but this small line spraying into the overflow (left above the water) will empty quickly and allow air into the line, stopping the syphon, and preventing any floods or tanks draining.

Presto - no risky (total crap IMO) cheque valves, no tank floods/drains, no return lines visible above the tank, no powerheads, and no closed loop.

If you need a more detailed description let me know. If you want help building such a set-up let me know. (or with any plumbing). You will need to accound for head-loss from the upper loop that prevents the syphon. It is easy to make a very effective assembly like this.

Cheers, and hope that helps?

Chris

[shrimpchips]

Utilizing the return flow really isn't the best way to get flow throughout your tank - it really should only serve to return water from your sump. Flow in tank should be a separate dedicated system, unless we're talking nano tanks.

Any design that places the returns well below the water line will result in draining your tank - just wait, it will happen. Even if you have check valves (which invariably fail) and siphon breaks drilled (which can get covered over and fail) and any other numbers of redundant systems, at the end of the day, I wouldn't have it in my home. $200 - $400 of plumbing and pumps now could (or will) save $10 - 20000 of water damage later.

Edit (Chris posted before me): With the piping going 24" below the water line to reach the bottom of the tank the amount of backflow (siphon) it will create will be very strong (the minimum size of the returns are probably 1/2", more likely 3/4" each). Even with siphon breaks, wouldn't the plumbing not stop draining right away as it takes a while before the amount of air that can be sucked in through the hole through the venturi effect will be sufficient to break the siphon. Either that, or you have a lot of large siphon breaks installed, which would really defeat the purpose of the returns.

Could you drill holes (~5mm diameter) in the eurobrace every 24" or so and use them to zip tie/otherwise secure the piping to the undeside of the eurobrace?

[Funky_Fish14]

I definitely agree with Shrimpchip's first point, that water flow really should have a system separate from just the return.

Responding to you, Shrimpchips:

Im not sure what 24" you are talking about? The 'region' of water that produces the backflow would be the part between the pump and the high point. (Same as in any system). It would take only a small amount of air in at the top of the upper loop to break the syphon. Infact it depends mostly on placement of the hole where the air comes in and the size/length of that upper loop. If there is a large section horizontally oriented in the top of that loop, then I could see a problem, but with a small upper point to the loop (by loop I mean an upside down U, in whichever shape is the most convinient for the situation), the air would be drawn in and break the syphon quickly (assuming the air-hole is large enough, which should obviously be tested).

I am absolutely certain that this could be done with less than 1gallon of water (from the back-syphon) draining back into the sump even with two return lines in such a way. (ofcourse with the anti-syphon holes, the part between that and the pump will entirely drain, but I mean less than 1 gallon to break the syphon, the rest of the water quantity depends on the amount of plumbing/size).

+ Setting this up correctly, there is no way any part (anti-syphon hole) sould become clogged. And confirming that (on any system) is simply part of regular maintenance.

Cheers,

Chris

[shrimpchips]

FF, yes, you're totally right. I forgot about this:

. . .as you go back toward the overflow, you bring the 'return line' back upward to above the waterline in the aquarium. . .

[dpg]

That may be it, thanks all

[kien]

Unless they are fairly large the anti siphon holes can and will eventually get clogged over time. I used to have them on my return nozzles to break siphon and had to increase their size a few times until I reached about 5mm I think. Even that clogged over time with various algaes :(

Anyway, as mention already you can guarantee their effectiveness by regularly checking them. I on the other hand got fed up with that added maintenance. It was just "one more thing" to pay attention to, maintain and support on what is already a complex system.

Anyway, just thought I'd throw that out there.. You know, since Mr. Murphy is such a big fan of out hobby and all :neutral: In the end I just let them clog up for the last time and instead built a bigger sump to support the extra 3 gallons to siphoned out from the return nozzles.

[Greenmaster]

This is what I am doing... still waiting for my hole saw to show up. I will be dividing my return into 2 flow accelerators coming through the back wall.
My overflow's final drain point will be slightly lower then this so it will not add any "extra" water to the sump if the pump fails.

http://i737.photobucket.com/albums/xx18/Greenmasterone/Return.jpg

[dpg]

What pump will you be using with that eductor?

[Greenmaster]

It's a 1" line that gets split into two 3/4" flow accelerators. I will have two of these for my 320g tank. The pumps I have are 1250gph but with the 6' head it's about 1000gph per pump... I have two pumps.