Which tank design do you like better?

[imcosmokramer]

Originally Posted by sphelps

1 is the standard, a tank builder will question the reasoning for design 2.

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.

[reefgirl189]

I like design #1.

[CherylMcKay]

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

[imcosmokramer]

Originally Posted by CherylMcKay

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.

[scubadawg]

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

[naesco]

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

[Dive_dry]

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

[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