another glass thickness question

vi3tekk

Feeder Fish
MFK Member
May 18, 2008
15
0
0
Seattle
can 1/2in thick glass be used for a plywood tank of 69in long by 36in high by 48 in deep as a viewing window?
 

Grant427

Feeder Fish
MFK Member
Jun 11, 2011
124
0
0
Alberta, Canada
From what I've read your safe for sure until 28" tall, but depends on your tank depth. For example if your glass panel is 30" tall you may be alright if it is raised off the bottom a few inches, but if it's on the bottom of the tank maybe not because there's more pressure. Height is the determining factor with the glass thickness. My glass panel is 31" tall, but raised off the bottom a few inches. It doesn't matter if your tank is 48" deep or 12 feet deep, the pressure on the glass remains the same so long the height stays the same.
 

Pharaoh

Administrator
Staff member
Administrator
MFK Member
Feb 18, 2008
17,566
171
1,097
Indianapolis
Absolutely not. You will need 3/4" at a minimum.
 

vi3tekk

Feeder Fish
MFK Member
May 18, 2008
15
0
0
Seattle
ah ic. can i use it if i only fill the water up to 24" the glass will be at the bottom and there will be a brace on top at the 24" mark going from left to right
 

vi3tekk

Feeder Fish
MFK Member
May 18, 2008
15
0
0
Seattle
or can i use a bracing in the middle of the length to help support basicly turning it into two viewing windows but just one peice of glass. like a 2x6 or a 2x8 brace in the center forming two square windows
 

Grant427

Feeder Fish
MFK Member
Jun 11, 2011
124
0
0
Alberta, Canada
You can always ask your glass supplier about it as well, the glass manufacturer I talked to said 10mm would be safe for my 31" height, I went with 12mm just to be safe.
 

Rivermud

Candiru
MFK Member
Dec 14, 2007
980
14
48
Idaho
I'm going to give you a few recommendations here as you may have meant 96 inches instead of 69. Regardless of what people say the length of the aquarium must be considered as well as the depth (vertical).

96x48x36 (safety factor of 3.8 unsupported/rimless)
Side thickness: .93" or 23.66mm
Reverse Calculation for 3/4" glass: 2.5 safety factor
IMO 3/4" glass should be safe enough in a supported plywood tank with top bracing

Fill to 24" 3.8 SF
Side thickness: .51" or 12.88mm
Reverse Calculation for 3/8" glass at 24" water depth: 2.1 SF
IMO 2.1 is low on the safety factor but can be used properly braced.

If on the other hand you were doing a 69 inch tank....
At 36" using .625 or 5/8" glass would give you a safety factor of 2.0, again that is low and I don't personally like it. However you may be able to find 18mm glass and that would give you 2.54 SF. the recommendations for 24" are the same as above.

Hopefully now you can make an educated decision. GL

http://www.monsterfishkeepers.com/f...rmuds-Glass-and-Acrylic-Calculator-(it-lives)
 

Rivermud

Candiru
MFK Member
Dec 14, 2007
980
14
48
Idaho
You can always ask your glass supplier about it as well, the glass manufacturer I talked to said 10mm would be safe for my 31" height, I went with 12mm just to be safe.
Just to let you know, your safety factor at a full 30 inch fill is 1.69, your safety factor at a 28" fill is 2.08.

I used your tank dimension for your posted build.
 

vi3tekk

Feeder Fish
MFK Member
May 18, 2008
15
0
0
Seattle
ah ic the aquarium was going to be 69 inches long and i was thinking if i can fill it up to the 24inch mark or as high as i can but still keep it safe. i wanted to do kind of like a vivarium type aquarium thats why it would be 48 inch wide so that i can build in the back. would be it be safe to fill to the 24in mark? what does a 2.08 safe factor mean?
 

vi3tekk

Feeder Fish
MFK Member
May 18, 2008
15
0
0
Seattle
what should the safety factor be at? my 3 year old daughter loves hanging out in the fish room and she sometimes talk to the fish and slap the glass lol when i use the program and set the height to 24in mark i get a safety factor of 3.2 at 12mm glass. is that enough?
 
zoomed.com
hikariusa.com
aqaimports.com
Store