Which tank design do you like better?
 

Design 1.

http://i81.photobucket.com/albums/j2...ght-side-1.jpg

http://i81.photobucket.com/albums/j2...24/front-1.jpg


Design 2.

http://i81.photobucket.com/albums/j2...overflow-1.png

http://i81.photobucket.com/albums/j2...overflow-1.png

http://i81.photobucket.com/albums/j2...overflow-1.png

Personally I would go with design #1.

#1. just in case you want to cover up the overflow.

Design #2 For me. It looks more "finished" rather than an "add-on" overflow.

1 is the standard, a tank builder will question the reasoning for design 2. Also I'd make the overflow extend down further, not much room for standpipe design.

reasoning for design 2:

1. might be stronger since there return holes are not drilled in a 5x5 section on the top left/right of the pane
2. improved surface skimming

but don't worry, I have reasons for design 1 as well, lol.

I like design #1.

I like design #1 as you wouldn't have go over the top somewhere for the returns.

huge + for #1.

in #2, the would go right over the wier and then to the left or right. The two outside holes would be the returns.

Design 1 is actually stronger, the side pane has virtually no bending stress or membrane stress (from pressure) where the return holes are located. In addition the overflow box adds strength. In design 2 there is a stress concentration factor at the radius where the front pane extends to the overflow box. If the radius is the same as half the diameter of the return holes it will have the same concentration factor for stress but the difference is that particular area does have much higher bending stress from the long length of the front pane of glass, especially if the tank isn't braced. In addition that corner radius is likely going to be smaller than the hole radius, the smaller the radius the higher the concentration factor meaning higher stress.

As for improved surface skimming, you may be right but 20" is pretty big already. I good alternative if this is what you're looking for is take design 1 and increase the length of the overflow and move the return lines into the overflow like design 2, then you accomplish both your goals.

Design #1, That's the way my tank is being done in the next 2-3 weeks, with eurobracing

#2 It looks longer.
If you choose #1 make the length 6 feet that way you can keep tangs.

i like #2 as that is how i am building my tank but on the long side 72" :mrgreen: lots of surface skimming is good

Do you mean extend them, but not all the way to the ends? I'm going to have a tee and an elbow in there for each of the three drains, so I have to make sure there is enough room.

I like #1
In #2 If your return is under water like that you will need to also figure out a way to stop the syphon when the pump shuts off

I would use a lockline to move it to the surface. It will be higher than the water level (or right at it)

I like #2 better. Technically it should be stronger since you don't have a corner cut into the glass that will be a stress point(even though there's very little stress with 1" of water). Lots of people with #1 though that works great for them.

Love the size of both though, very wide. Will make a great reef.

i like design #1. only cause its pretty much exactly what i have. you can see pics in concept's thread (pics 11 and 12). it is 60x30x24h

http://www.canreef.com/vbulletin/showthread.php?t=82418

Numero Uno

I am going to throw a problem in here. design 1 has two inside 90 degree corners in the back pain, which are inherent stress points in cut glass. so in-fact tank 1 could actually be weaker on the back.

as for looks tank 2 will look much cleaner from the front and a coast to coast overflow is nice for a few reasons, better surface skimming and also because of the extra length it has more volume. the only issue I have is how are you doing your returns in number 2

my vote is for design 2

Steve

#2 for me. All you have to do is have your everflow notch for the returns and use lock line. that's what I did. My returns are drilled in the bottom and they come up, then bend into the tank under water. I even have acrylic on top to finish off the look.

Here's a pic.

http://www.mattdean.com/build/durso.jpg

http://www.mattdean.com/build/acrylic1.jpg

Design 1 is stronger guys, this is the problem with design 2
http://i11.photobucket.com/albums/a1...lps/tank-2.jpg

The notched side in design 1 is not only supported by the overflow but it's signficantly shorter in length than the front... You know whole Mc/I deal, M being FxL....

Pretty much yeah, if you stick with a notch you'll need at least 2 inches on each side so it can be cut properly. If you want to extend the box the full length then skip the notch and lower the height of the entire side pane but keep the overflow box separate and not part of the front pane. Alternatively you could also just extend the length of the tank and go with an internal overflow box on the side.

Also when I say front and sides, I calling the pane with overflow the side and 5x2 pane the front.

Matt has the right idea there, essentially an internal overflow on the side if you're looking for a full width overflow.

Design #1 all the way. Not a fan of the up and over look. Doing the notch for design 1 is a pain if you do it yourself and a little more pricey if that glass shop does it. Design 2, if you do the long sides plus the overflow as one piece you are still having to put a notch into the glass. If you don't do it as one piece, you'll have some funky silicone work at the top edge that will be ugly and weak (gap between panels should be 1 mm). I would worry about stress points on the back glass if you do the notch so long as your glass is the right thickness. We over engineer the glass thickness as it is. Just doing a back of the napkin calculation on stress around the notches you're still at a safety factor of 4. I did a notch on my tank, couldn't be happier.

Exactly. just make the whole tank longer and put the overflow inside, top to bottom. I painted the sides black and it looks slick and works flawlessly. Also gives you more water volume. All holes drilled in the bottom and nothing going over the sides or sticking out. It's as clean as it gets. AND, no worries about weak spots. It's as strong as it gets.

interesting. How do you clean the tall overflow box?

sorry didn't see that the sides were all one piece, I assumed it would be the normal of a box add on. I would recomend number 2 still with the modification that the over flow be added to the tank. just get the end of a normal designed tank made 1/2" shorter than the other end and sides, then build a box oneto the end to make your over flow box.

Steve

You're supposed to clean the overflow box? Really? WTF?!?!?! LOL!
I just siphon it out every blue moon. I can get my hand in there easily. Actually, I have rock in the overflow box. :biggrin:

I honestly can't imagine having an external box and pips coming up. It just seems crude and unattractive to me.

yes, if you have detritus in your overflow (which you do), it's a good idea to siphon it every once in a while.

As for "crude and unattractive"..first that's your opinion which (second) is based on the assumption that it will be visible :D

This type of overflow is much easier to maintain and troubleshoot if anything goes wrong.


Steve, Yes, I'm sure the box will be an add-on if this id the final design. I just didn't feel like messing with the rendering to reflect that. Yeah, I'm lazy.

Ok. You do realize I was joking about cleaning the overflow, don't you?

And yes, I'm obviously assuming that It will be seen, hence my opinion-which is all I am offering, I never said it was a universal truth-and I did say it was crude and unattractive to ME. Again, just my opinion.

Cool, opinions is all I want. Thank you.

(I do know many people who don't clean their overflows, especially on standard tanks where it's not as accessible; so no, I did not know you were joking)