DIY large tank tips

[bues0022]

I've been tossing around the idea of "graduating" to a much larger tank. Currently I have an oceanic 58 and 30 plumbed together. I've seen some of the large Marineland tanks and absolutely fell in love with them. Now, my neighbor owns his own glass company, and tells me he can build me a tank for a fraction of the cost by using "scrap" from large industrial jobs. I'm almost positive I want to go with 66L x 36W x 27H. That puts me at about 275 gallons. I've crunched some numbers, and with 1/2" glass I have a safety factor of 3.0 (3.8 is ideal, but a standard 210 has a SF of only 2.0) - assuming I have the bottom fully supported, which I was planning on doing. Not sure yet on the overflow design, running some calculations on that still. My biggest questions are with respect to the actual build of the tank. He's built some tanks, but from what I can figure nothing with this size to it that isn't literally built into a wall. I've done a lot of reading about building tanks, but not much covers large tanks like this. Any lessons to be learned and things to watch out for? I plan on being there while he's assembling the tank so I can help out and keep an eye on things to make sure it goes smoothly. I am going to have ~3" eurobrace overlapped like mcliffy2's tank - overlapped at the corners. I also am going to have an "internal eurobrace" along the bottom inside the tank. The purpose of this is to give a little more surface area for the silicone bond (do you think this is necessary?) Additionally, I'm going to have a "rim" welded from probably 1 or 1.5 angle aluminum. This will be siliconed in place during the build.

Anything else that I should be thinking about, or worried about? He's a glass guy so I'm trusting that he can make a good silicone joint (of course using aquarium silicone - black). Tips would be appreciated from those with more knowledge than me! Thanks!!

 

[bues0022]

anyone have any tips for me?

 

[Nanook]

I would be very leary of him as a quality tank builder.

 

[LauraCline]

If you do decide to do this, make sure you water test it outside first. With over a ton of weight just for the water alone, if it failed or seriously leaked it could be catatrophic. That is enough water to do serious damage to your house. Is the glass tempered? I know they use tempered for extra strength. Also for that size tank and glass thickness, you might want to go with starfire because it is so clear. If it does leak or fail and flood your house, is he offering any kind of warranty?

 

[bues0022]

What makes a quality tank build different from a sub-par build? Isn't it just the quality of silicone seal that they can achieve? Glass is glass everywhere, so I was assuming that the seal is where the quality comes from. Prepping the glass, quality of seal, and finishing it all off. I am having a 3 inch eurobrace, and a metal top "frame" with two cross-braces. This should significantly reduce the stress on the silicone seal. I am also tossing around the idea of making a bottom "frame" too, but I think instead I am going to capture the bottom of the tank inside my stand framing. I'm trying to take the right precautions, but am looking to you guys for more. The glass will not be tempered. I know it has added strength, but is more suspect to point-loading problems. Standard glass is more forgiving to imperfect conditions in support.

I'm definitely going to test it with FW outside first! I'll check with him about a warranty and the "what if" something should fail.

Also, any reason why I should go the extra 6" to a 6' tank rather than 5.5', or even 5'? Thoughts on size?