Hi! I'm Tony, currently stationed here in Saudi Arabia, and I'm fairly new to the forum but I'm posting here in behalf of a friend who's being frustrated by a DIY tank of his that's been causing trouble. It's because of that problem that I found this site, and we're both hoping someone could help.
My friend's built a 9.1 x 2.0 x 0.8 meter glass aquarium. That comes around to 4000 gallons if we figure correctly. The glass is 31mm triple-layer laminate panels, with each panel at 2.0 x 2.0 meters. (For the long sides, that is.) The joints are supported internally by 10cm-wide laminated glass strips and silicone seals, externally by a frame constructed of 10cm-wide, 10mm-thick U-beams.
After the aquarium had been assembled, the silicone was left to cure for 30 days. Then we filled it up and left it full for 15 days to see if any leaks would show up. No leaks were found, so we assumed it was fit for use. We emptied it for cleaning, then refilled. After two days, traces of a leak had shown somewhere around the midpoint.
So we emptied it again, stripped the secondary seals inside, and laid down a new layer of silicone. Then we set this new seal to cure for 15 days as well. When it was all good and dry, we filled the tank up again, but in a few days, the leak had returned and in roughly the same area.
There wasn't any bulging detected on the glass, so we've no idea what else to follow up on. We've tried to find consultants here, unfortunately, no one has experience making tanks this big.
Just to give you a feel for the size of the thing:
And to illustrate the measures that I've mentioned before:
And, THE LEAK:
My friend has stated some concerns regarding the silicone seals that were used (both primary and secondary). He's asking how big a bead of silicone you need to use for something this big, and if too much silicone could in some way cause the leak. This is 'cause he's seen aquariums roughly the same size in other countries that didn't use a lot of sealant.
I hope you guys could help, or at least point us in someone who can, as this project has been giving us a lot of headaches for too long a period already. Thanks in advance!