Which tank design do you like better?

[sphelps]

Originally Posted by imcosmokramer

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.

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.

[imcosmokramer]

Originally Posted by sphelps

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.

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.

[e46er]

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

[imcosmokramer]

Originally Posted by e46er

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)

[Lampshade]

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.

[therealshark]

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

[Nano]

Numero Uno

[sphelps]

Originally Posted by imcosmokramer

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.

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.

[StirCrazy]

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

[mattdean]

#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.