First Tank Build - 400 Gallon

[Rivermud]

in the interest of keeping this thread dedicated to its original intent, do you have a thread for your build yet? If not you can pm me with your idea and I will help crunch numbers with you.

 

[Grant427]

've wrote about and done a lot of work with glass thickness as well as acrylic thickness. The industry set the standard safety factor at 3.8. If you put a lot of the aquariums made commercially up to the calculator i built you can reverse engineer the safety factor.

20g High = 20 1/4 x 10 1/2 x 23 3/4 = SF (1/4 glass) 2.2 recommended glass thickness for 3.8 SF is .33
55g Standard = 48 1/4 x 12 3/4 x 21 = SF (1/4 as per Aqueon) 1.5 recommended thickness is .40

So, we know that the 55g tank bows like mad without it's center brace thus we can assume that they are fudging their own safety factor due to bracing. This means the SF rating of 3.8 is meant for unsupported all glass panes. As you probably have noticed, a LOT of aquariums are built with center braces. The standard 90 gallon is a 48" long tank by 25 inches high. Most of the time it is built using 3/8's or 10mm glass giving it a SF of 2.1 or 2.34 while the recommended thickness is .5. There are tanks that are built that do actually match or exceed SF ratings but they are few and far between.

My personal DIY is filled to 22 inches of depth with 1/4" glass giving me a SF of 1.3. It's survived for 3 years; multiple fish hits, driftwood hits, moving, etc.. It's fully framed with plywood and has a center brace. The pressure on the tank isn't going to make the glass flex due to the bracing thus the major reason for the SF rating of 3.8 is out of the window. To be honest, when compared to a 55g I feel a whole lot safer with my tank than i ever will with a 55

At any rate, it's up to each person to decide the level of risk they wish to take. The calculator I designed can reverse engineer numbers for you based on the dimensions given for both glass and acrylic. Feel free to use it and play around.

http://www.monsterfishkeepers.com/fo...tor-(it-lives)

Yes I definitely agree with your math, it depends alot on construction. I believe that if your glass is framed with wood and center braced that you good get away going quite high with 1/2" glass, bowing to the point of breaking would be the only way I could see it failing. If your glass is in a frame that prevents any bowing how would it break? When I bought my glass they had said it'd withstand pressures well over 100psi, the pressure on the bottom part of my glass in the tank is 1.3psi, now obviously I wouldn't believe you window could be 15 feet tall, however I would think 4 or 5 feet no problem if your glass is properly supported. For my 32" with 1/2" glass I had no issue's, it survived a few good hits, one when a chunk of slate was knocked over.

It's 100% the risk you feel comfortable taking, personally I'd try 1/2" up to 4', but not over that until I proved 4' was safe.

 

[bubbles123]

Sorry to hear about the problems. Glad to hear another build is coming.

 

[Rivermud]

Yes I definitely agree with your math, it depends alot on construction. I believe that if your glass is framed with wood and center braced that you good get away going quite high with 1/2" glass, bowing to the point of breaking would be the only way I could see it failing. If your glass is in a frame that prevents any bowing how would it break? When I bought my glass they had said it'd withstand pressures well over 100psi, the pressure on the bottom part of my glass in the tank is 1.3psi, now obviously I wouldn't believe you window could be 15 feet tall, however I would think 4 or 5 feet no problem if your glass is properly supported. For my 32" with 1/2" glass I had no issue's, it survived a few good hits, one when a chunk of slate was knocked over.

It's 100% the risk you feel comfortable taking, personally I'd try 1/2" up to 4', but not over that until I proved 4' was safe.

Actually the pressure on the sides of your tank is not the same as the psi rating at depth. the following is shamelessly taken from a post at aquaria central

One think you need to know about pressure is that it works in “pushes” in every direction equally, so if the pressure is 10 psi, that means that on the sides of the tank, there are 10 psi.

To find the force on the side of the tank you simply need to multiply the area of the glass by the pressure. But wait, its not that simple, the pressure changes with depth. This is why the calculus is needed. If you under stand it, its included in the next paragraph. If not, then just ignore it and use the equation in the last line.

Note: I cannot make an integral sign, so I’ll use int(..) instead.
F = int( dxWxh dh) dh refers to the variable being integrated with respect to, basically.
F = ½ xdxWxh^2

To find the force on the side of the tank, just plug the numbers into the above formula.
Example (front or back walls):

10 gallons:
F= ½ x .036x20x12^2
F= 52 lbs.

29 gallons:
F= ½ x.036x30x18^2
F=175 lbs.

55 gallons:
F= ½ x.036x48x20^2
F= 346 lbs.

This doesn't factor in certain things such as deflection and the multiplied force of the pressure at the apex of the bow. This is why 55 gallon tanks are braced. This is also why the industry standard of 3.8 only applies to rimless non braced all glass aquariums and not to supported and braced enclosures. At 48" of depth we are below a 1 for sf, I'm not comfortable with that. I usually recommend 2.2 to people as i find it's quite safe for plywood builds however I am comfortable down to 1.3 as per my own build.. i don't think i'd be very comfortable going below that. that would put my minimum around 18mm or 3/4". However at 36" .5" glass has a rating of 1.3.... just food for thought.

 

[stempy]

This is my worst mightmare when I do my fill, sorry to hear about the leak Have you torn it down yet to find what went wrong?

 

[Grant427]

http://www.monsterfishkeepers.com/f...er-and-Try-Again-650-Gallon-Build-(2-Viewing)

 

[RichardKranium]

Sorry to hear and Love the paintings Awesome!!!!

 

[Abruskin]

All done with the Liquid Rubber, covered the whole thing with 3 coats with a brush, to get the same mills with a roller seems like it'd take at least twice as many coats. Hoping for my glass to be in next week and filled by next week or the week after. Everything is looking real good, didn't think there was much point in taking more pictures of the tank now since it looks the exact same as after one coat. The mancave is starting to look like a mancave now!

View attachment 732236

Finally got the painting my girlfriend did for me! Let me know what ya think!

View attachment 732237

Updates asap! Happy New Year!

Your girlfriend painted that??? That's unbelievable. She has a great talent and so do you! Love the tank build


Sent from my iPad using MonsterAquariaNetwork app