Tank Exploded! Ka-BOOM!

[fish_4_all]

The weight is close, I don't remember the calcs I had seen but it come out to about 10.5 pounds per gallon with substrate, glass weight, and water weight. Someone on here gave me the numbers a long time ago. My memory is really bad. I will look and see if I can find it, would be from 2 years ago or there abouts.

 

[Cartagena]

darn.
That's one messy cleanup.

It put giant scratches in the wood floor that I just refurnished a month ago.

It knocked a whole in the stucco in the wall which will have to be patched and repainted.

It tore a small whole in my brand new chair.

It completely destroyed one of the small tables.

There was about an inch of water on the floor.

The ornaments that were inside the tank and all smashed.

I have not tested the pumps yet but they look ok.

 

[Lonewolfblue]

Well this is interesting!

Yes, the bottom piece of glass sat flat on the foam without a gap. There was no elevation around the sides or front.

Yes, those dimensions are correct. 80 tall, 120 long and 40 wide. He used 8 millimeter glass. He said the new one will be 10 millimeter! I guess I better call him to change this.

I estimate the water weight at about 845 pounds. It would be equal to 101 gallons.

Thanks for the tips.

Yup, you better call him and tell him you want a minimum of 12.7mm glass.

 

[src]

Also, for a tank that size, I believe the bottom should be made of tempered glass.

 

[BillD]

For a tank built with sides on top of bottom, having styro for it to sit on is absolutely the correct way to do it. The tank did not fail because of that. something else was wrong, perhaps the thickness of the glass (most likely), although it looks as if it was euro braced.The problem was also not caused by the bottom not being tempered glass. While suspended bottoms are favoured by commercial manufacturers, for a number of reasons, they are not better than a properly supported bottom. Tank manufacturers can't guarantee that the end user can/will properly support the bottom, hence the floating bottom, which takes it out of the equation. Those tanks typically set into a moulded one piece frame to support the edges, and protect them. For one thing, a suspended bottom can be cracked by a point load, caused by a rock pressing on a single grain of gravel.

 

[SparKy697]

It seems that the idea of the bottom of the tank sitting flat on the foam might just be the cause. Since you can not account for varying density in the foam there might have been an uneven distribution of weight that the glass could not hold up to. The fact that there was glass behind the stand also seems to point to the bottom breaking and "floating" the rest of the tank onto the floor.

What kind of foam are you using? It looks like it is white in color. Is it the kind that looks like it is made up of little balls pressed together? If so that is not a very dense type of foam and often is quite soft. You may want to look for something more dense. In my area you see a number of different kinds of foam that is often colored pink or blue. It is used for insulation in buildings and other things. I believe it is called closed cell foam board and is quite rigid. You may have better luck with something like that.

 

[Sicklid]

I totally agree with BillD... I always recommend Styrofoam underneath when the tank may be out of level, it must have some give to help the tank self-level... nothing wrong with that. I don't think you need thicker glass, either, 8mm is almost 3/8 inch, but bigger is definitely better. Those dimensions seem close to a 55 gal or so, for which 3/8 is fine if it is properly braced. I would hate to lift my 55 gal if it was made from 1/2 inch glass!

I am more concerned with HOW the seams were laid out, as in, did the sides sit ON the bottom or did the bottom fit INSIDE the side dimensions? Does this dude build a lot of tanks, or is this his first? Did he get the silicone BETWEEN the glass or did he just run a bead up the inside corner? What type of silicone did he use? That is the stuff I would question.

Also, how long did it cure?

 

[Lonewolfblue]

]I totally agree with BillD... I always recommend Styrofoam underneath when the tank may be out of level, it must have some give to help the tank self-level... nothing wrong with that. I don't think you need thicker glass, either, 8mm is almost 3/8 inch, but bigger is definitely better. Those dimensions seem close to a 55 gal or so, for which 3/8 is fine if it is properly braced. I would hate to lift my 55 gal if it was made from 1/2 inch glass!

I am more concerned with HOW the seams were laid out, as in, did the sides sit ON the bottom or did the bottom fit INSIDE the side dimensions? Does this dude build a lot of tanks, or is this his first? Did he get the silicone BETWEEN the glass or did he just run a bead up the inside corner? What type of silicone did he use? That is the stuff I would question.

Also, how long did it cure?

Very good points there. I also don't think it's because of the styrofoam, as places like glasscages.com even recommend it. I've emailed them for the 300G I want, and they said it's the regular white styrofoam is all you need (3/4"), to help get rid of any small uneven areas that can cause stress.

Here's the dimensions in inches....
47.3 inches long, 15.7 inches front to back, 31.5 inches tall = 101G
Thicker glass would be needed, as the weight of the water would be twice that of a 55G for close to the same footprint. Also, if the bottom was floated, would the silicone actually be able to hold that kind of weight? I personally would not want a floated bottom, I would have the sides on top of the bottom and place the tank on styrofoam.

 

[BillD]

I always use the white styro, as it is a little softer than the pink or blue, and I believe it absorbs the discrepencies better. It will not correct an out of level situation, but will help with any discrepencies in flatness. The floating bottom aeems to work ok, with tanks that have a plastic rim, but if the tank is rimless, like all my homemade tanks, a floating bottom would put the total weight of the tank on a very small surface area.

 

[fish_4_all]

I don't what kinds of foam he is using but ito me it sounds like it is a super dense and not the typical foam. I have seen this stuff locally and it is so dense it takes a good sharp blade just to have a chance to cut it.

I for one would like to see the instructions for a foam bottom supported tank. I have not been able to find them in any search I have ever done. I have also definately not seen any tank instructions where the side glass sits on top of the bottom, the bottom was always inside. If it can be done I could build the tank I want the way I want and not have to deal with a floating bottom.

As for the glass thickness, gallons has nothing to do with it, it is the height of the tank. Anything over 24 inches requires the use of 1/2 inch glass to support the extra weight of the water in the column, especially in a tank pushing 100 gallons and 31 inches tall. I supposed a 20 gallon 31 inches tall would only need 3/8 but not 100 gallons. Technically you could have a tank of well over 400 gallons and only use 1/4 inch glass if it was only 14 inches tall although I wouldn't recommend it.

 

[Sicklid]

Oh, sorry guys, I did not realize it was that tall! Wow, yeah, you do need heavy glass, and I would love to see a rim on that puppy too... Silicone is amazing stuff, but a rim and bracing is the real deal.

Fish 4 All (great name!) I always see the good folks at wet web media instructing people to use styrofoam under the tank when it may be out of level... I trust those peoples advice. Styro would not just give in one corner like that, unless all the weight was placed on that spot. But a tank's weight is dispersed evenly across it, that is the point of using the styro:

http://www.wetwebmedia.com/aqstdleveling.htm

 

[BillD]

I for one would like to see the instructions for a foam bottom supported tank. I have not been able to find them in any search I have ever done. I have also definately not seen any tank instructions where the side glass sits on top of the bottom, the bottom was always inside. If it can be done I could build the tank I want the way I want and not have to deal with a floating bottom.
/quote]

I have built 5 that way including the first one I built, 40 years ago, and which I am still using. I also have 2 tanks from the 60s and one from the 70s built this way.
The styrofoam, will give where needed to take up differences in flatness, between the bottom of the tank and the support surface it is sitting on. As an example of how this works, I have some steel tubing stands I built. They carry 2 homemade, frameless, 48" x 12" x 12" tanks. When I first placed the tanks on the stands, the centre part of the tank was not being supported. I added 3/4" styro and when the tank was filled, the styro gave on the ends, untill the entire bottom was supported; the gap in the centre was about 3/16".
If the stand was out of level, the tank would still be out of level, but well supported.

 

[Cartagena]

The "tank builder" is now saying he will make it out of 20mm glass. This should work, no?

 

[Sicklid]

That is near 3/4 of an inch! I think it would withstand an bullet

 

[Lonewolfblue]

That is near 3/4 of an inch! I think it would withstand an bullet

And it will be HEAVYYYYYYYY, LOL.

Yes, that will work just fine.

 

[jsoong]

One small note - when trying out any DIY tank parts, I always test the contraptions outside! I would fill up the new tank (after it has fully cured) outside & give it a few days to see what happens. (Of course, for a bottom supported tank, you would have to find a level concrete pad & put it on styrofoam.)

A wicked thought - have the tank builder test it in HIS shop! If it breaks, HE gets to do the clean up!

 

[Cartagena]

Yes, I am absolutely going to test this outside before setting it up inside. I live in a South American country with a high level of unemployment. This results in a lot of people claiming to know how to do jobs that they don't. I suspect my tank builder is one of them. I would use a different guy but the new guy would probably be the same.

 

[severum mama]

Make sure this guy either Euro-Braces the top, or uses the standard top frame with at least one center brace across the top center of the tank. I don't know a whole lot about structural integrity, but I do know that all large mass-produced tanks (at least in the states) have at least one center brace and a frame around the bottom as well, and I've seen many custom tanks with a Euro brace on the top. The custom tanks were also braced on the bottom, from the inside, with the same technique used for the Euro brace on the top.

 

[BillD]

The tank that kaboomed was euro braced (see picture), and with glass that thick it would not need a centre brace (if it is euro braced).