The tanks internal measurements W 81 H 33 D 31 just ran those through a calculator and came out with 358 gallons or 1395 litres. So yep going to be some weight in this setup. Thought the capacity was only around 330g, guess I got a little carried away some where.
Before starting this project I looked at what overs had built in much larger tanks and as you say some build frames of 4x2 to strengthen the ply while overs just seem to go with the ply as it is
I found a guy who built a 500g tank with no aditional support for the walls and it all seemed to work for him. Another that built a 600g and braced it with 4x4.......
The screws you can see in my pix are 2" apart and the edges are sealed with a water proof type of liquid nails. The water proof part of the glue shouldn't make much difference as if the water gets to that point I'm screwed anyway. But water proof was only a few cents more so why not.... I think to this point the joins are as sturdy as I can make them but the contact area of the ply sheets is very small so I will be running 2x2 along the inside joins to beef up the contact area, again screwed and glued. Also a 4x2 vertically up the centre of the back wall to meet the middle brace. Because I'm using 2 pieces of glass I'm going to treat the tank like I'm making 2 smaller tanks and joining them together, so the major bracing will be the middle section where the glass joins. I'll post pixs as I do this and then if it still doesnt look strong enough I ll look at other bracing options.
Before starting this project I looked at what overs had built in much larger tanks and as you say some build frames of 4x2 to strengthen the ply while overs just seem to go with the ply as it is
I found a guy who built a 500g tank with no aditional support for the walls and it all seemed to work for him. Another that built a 600g and braced it with 4x4.......The screws you can see in my pix are 2" apart and the edges are sealed with a water proof type of liquid nails. The water proof part of the glue shouldn't make much difference as if the water gets to that point I'm screwed anyway. But water proof was only a few cents more so why not.... I think to this point the joins are as sturdy as I can make them but the contact area of the ply sheets is very small so I will be running 2x2 along the inside joins to beef up the contact area, again screwed and glued. Also a 4x2 vertically up the centre of the back wall to meet the middle brace. Because I'm using 2 pieces of glass I'm going to treat the tank like I'm making 2 smaller tanks and joining them together, so the major bracing will be the middle section where the glass joins. I'll post pixs as I do this and then if it still doesnt look strong enough I ll look at other bracing options.
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