Need advice building 45 degree angles

[Borre]

I'm in the planning stage for some oddly shaped aquariums, namely such which from above look like a diamond in profile, or a square with one corner chopped off at a 45 degree angle. I'm not sure how to silicone the panes together that form the 45 degree angle and I've come up with 4 different design possibilities (if there are more I'd appreciate it if they got pointed out to me in case they have any bearing in my line of thought).

I want the one design that is the safest, however, with aquariums, safe is always relative until you know the size and volume. So, the hypotenuse* pane that you'll see will be about 43 cm wide, the ones to its left and right will be 18 cm wide. The height of the tank is 35 cm, the volume in total something under 75 L. So it's not that huge really.

*(relative to the triangle that will get chopped off the base square)

If I call them 1 through 4 counted from left to right, then I'd personally prefer design 1 as that is the best looking. However, if you'd deem 2, 3 or 4 safer in some way I'd want to know and to know why. The arrows depict the direction of water pressure (just so there is no confusion). In all of the four designs there'd be four possible seams for the silicone to go, just in different spots. Of course this is only a 2D representation, in a 3D one there'd be the extra bottom seam, but that one is a given anyhow so we don't need to bother about that.

Thanks for any help!!!

 

[knifegill]

The glass should be cut to fall flush at the seams. Seal edge to edge. Barring that, the third option looks the sturdiest with silicon built up inside the notch.

 

[badreverend]

do you have the option of a frame between the panes? if not, I think flush would be the next choice also- I believe the reason flush would be better than the other options you had is because there is a greater contact area between the two panes

 

[bob965]

Those will all look gross and not be very strong. You need to miter the edges of your panels.

 

[Borre]

Thanks all for your input! During the day today I came up with a way to build a mechanically interlocking aluminium frame for this, so it will be quite stable. That means that I'll likely go with version 1 and that I might put aluminium strips over the seams on the front to hide the silicone.