Calfo Style Overflow boxes

Just go for an external durso if you want to go narrow. There are pics posted on the first or second page of my build thread, click my red house. Just make sure you can fit the bulkhead!
 
Hi, I do my external dursos and place some small overflow boxes to feed my deltec from the water surface, they work really good and they cost about 25 each one

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<a href=showthread.php?s=&postid=10878067#post10878067 target=_blank>Originally posted</a> by sayn3ver
i want to do about a 2ft internal horizontal overflow in my 40B. How narrow can i go?

You can go quite narrow, but if it's a permanent setup, you want to allow yourself enough space to get in there with something to clean it out every once in a while. It also depends on how much flow you have going through it.
 
"You can go narrow, but be able to fit the bulkhead in".

What is the thinnest one can go and still fit a bulkhead in? This is my first reef and my first attempt at a sump so i don't have any bulkheads in my possession right now to play around with myself, but i assume that there is a number out there.

gilprado,

how do you mount those acrylic boxes to the tank? Will silicone hold them to the glass? I was considering an Austin Ocean's overflow box but they want a ridiculous amount of money for an acrylic rectangle.
 
<a href=showthread.php?s=&postid=10897322#post10897322 target=_blank>Originally posted</a> by sayn3ver
"You can go narrow, but be able to fit the bulkhead in".

What is the thinnest one can go and still fit a bulkhead in? This is my first reef and my first attempt at a sump so i don't have any bulkheads in my possession right now to play around with myself, but i assume that there is a number out there.

gilprado,

how do you mount those acrylic boxes to the tank? Will silicone hold them to the glass? I was considering an Austin Ocean's overflow box but they want a ridiculous amount of money for an acrylic rectangle.

I made mine out of glass and went narrow, about one inch, without bulkheads. See pages 2 and 14 of this thread. I've been real happy.
 
<a href=showthread.php?s=&postid=10899176#post10899176 target=_blank>Originally posted</a> by brackishdude
I made mine out of glass and went narrow, about one inch, without bulkheads. See pages 2 and 14 of this thread. I've been real happy.


This is how I'm planning my next tank. I see no need for bulkheads there as I'm going with a permanent internal narrow overflow feeding into an external box for the durso, etc... So the water will just flow over the internal, then through a few drilled holes, into the rear external box.

like so:
overflow2.jpg



Pretty much just like brackishdude has shown in the posts he mentions.
 
Daemonfly.........out of curiousity, why put a box internal at all if you are going to put one outside, instead of just making the back wall a little shorter to directly skim the surface into the external box????
 
Easy. Making a long narrow internal overflow, then drilling a few holes, is a hell of a lot easier than making the back wall a little shorter. It's only 2 pieces of glass in my design, and I'm actually considering using just one angled piece to make a wedge shape instead of a box, so the edges aren't as visible.

The narrow internal overflow gives all the benefits mentioned of having a wide weir overflow without it taking up too much in-tank room like you would if you had the "normal" Calfo-recommended overflow.

The rear box wouldn't really take up much more room than the plumbing for any other system, as you can now just bring the plumbing up from the bottom of the rear box, instead of out the back and then down with elbows. It's there because the internal box would be too narrow for bulkhead use if any maintenance would ever be needed. It's not necessarily dead space either, it could be used to hold media, or even a small benthic zone.


Probably comes down to personal preference, really. I hate tanks that are too visually impaired with equipment showing everywhere. Most of the "Calfo-style" internal wide overflows listed in this thread also stick out too far into the tank, imho.
 
Fair enough...just curious. I have the back wall shorter on mine and a completely external box, wouldnt have it any other way and plan to change my larger tank out to the same thing sometime in the near future......but its a acrylic tank so a shorter back wall isnt much of a problem. I agree with you completely on the intrusiveness of some of the calfo style internal boxes.
 
Deamonfly,

GREAT IDEA re constructing the wier out of one piece of angled material rather than the traditional two !!

I always am chagrined when I realize how my brain is limited by what it has seen before: I never would have thought of your one-piece solution, but I think it is grand.
 
flyyguy, how is the back wall of your acrylic tank supported. Do you have a full top that covers the overflow as well, or are you just relying on the flange created by the bottom of the external overflow to keep the back wall from bowing. I'd love to see pics if you've got them. I was worried about the back wall bowing so I brought part of it up to meet the eurobrace, easing the strain right in the middle but separating it into two long overflows.
 
Woz......yeah...it isnt a a TRUE coast to coast as the back wall does meet the bracing for 6" in the center......enough to fit two 1" bulkheads at the top center of the back wall actually.......

A couple inches would have been plenty.

Its more for overall tankintegrity that holding that box on though. I simply have a lid that sits opn top of the box to keep light out for the most part

This is an older pic......I have since incorporated a "herbie" method of sorts on the overflow to quiet it down as my little mini dursos I created werent quite quiet enough......but you can get an idea of what my external overflow box looks like

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Yeah, I see. Looks very similar to mine actually, I left 6" in the center as well. The only difference is I made my top cover the overflow too.

Is that an OM-8 way? I've never seen one from the top, so I don't know if it's that or something else. That's sweet that you can mount it sideways if it is an OM.
 
ya...its a OM-8 way. I initially planned on a 4 way for this tank, but after setting up a 8 way on my 225, I knew I had to have the 8 way for this 90 as well. It took a little creativity to fit it all in there.

I just have a removable top for the overflow to keep light out. And it is easily removable so every so often I can vacuum out any detritus that collects in there as well
 
like so:
overflow2.jpg



Pretty much just like brackishdude has shown in the posts he mentions. [/B]

I really have been satisfied with my design, and even more satisfied that others appreciate the elegance.

You nailed it in terms of the simplicity, but I also have a heavy hood that needed support all the way around, so I couldn't afford to lower the back wall.

Consider adding an end piece to each side of the weir, and leave the weir short by about 2" on either side. Having the wier glass siliconed right to the tank's side glass is fugly, IMO.
 
I am still not understanding or maybe I am not being completely clear in my objectives.

I want an internal horizontal overflow box, roughly 2ft long, with NO outside box. Sure, I will want "durso" pipes going off the outside of the bulkheads. I assume I need bulkheads for this to work. Then this was my original question, what is the minimum depth(from rear glass of tank to front of overflow) that can be used with bulkheads. This will be a permanent setup, not just a temp tank.

The pictures on page 2 and 14 both indeed show a narrow overflow box, but they are running an external box which is something I don't want to do, mainly I do not trust myself enough to cut and silicone on a box to hold water externally(this tank will in my bedroom on the 2nd floor, so no unnecessary chances).
 
sayn3ver, if you do the durso through the wall like you're talking about the only room you need inside the overflow box is for the flange end of the bulkhead+the length of the elbow+room for a coupling of some sort so you can attach the elbow to the bulkhead.

So, I'd say,

1/2" for the blukhead flange
3" for the elbow (obviously this depends on the size of the elbow)
1" space so the elbow plus coupling can be removed from the bulkhead

That's like 5" max, and probably less. Just grab a couple fittings at Lowe's and dry fit it. Make sure you leave yourself some room to remove the downturned elbows in case you ever need to clean them.
 
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