120" x 48" x 48" tank using 1" acrylic - will it bow?

[daytonben]

The thickness is fine, the seams need dealt with. You could easily disassemble it, router off a couple inches of each edge and have it reassembled. It wouldn't be perfect, but it's a fair enough low cost solution.

 

[camaroboy8691]

It will bow, but there shouldnt be any outright failures, I work on a 72x36x30 that is built from 3/4" and there is no discernible bowing at those dimension.

on this 96long x 30 high by 48" wide how much are we talking on bowing ? i mean its made from a well known company so it should be ok right ? the seams are clean no bubbles or anything odd .....the top is also 3/4 thick and has only 2 big openings about 20" square on each end about 10" or more in from the edges . its a very beafy tank but now im worrying just a bit

 

[albano]

on this 96long x 30" high by 48" wide ...but now im worrying just a bit

C-boy, your tank should be fine, the tank mentioned in this thread is 48" high... a BIG difference in pressure, over your 30" tank

 

[Typhon]

IMO, even if the seams where perfect, the thickness is an issue. Depending on the amount of deflection you might see a great deal of craising(sp?).

When my tank was build, the builder said even with 3/4" side wall thickness I would see around 1/2" of bowing. And my tank is only 26" tall (96"W,48"D). So I decide to go with 1" side and top.

I wouldn't risk it.

 

[camaroboy8691]

C-boy, your tank should be fine, the tank mentioned in this thread is 48" high... a BIG difference in pressure, over your 30" tank

im sure it will be fine . i just get worried sometimes . and the more i think about the water and such . the water line on this tank is about 3.5" below the top of the tank . so the tank actually only holds roughly 530 gals of water since the water is not at the top of the tank . also . there will be alot of rock inside the tank that will displace alot of water also im thinking almost 100-125gals of water the rock my displace . so technically there is only about 400-425gals of water in this tank to push against the sides ..... so thats not that much pressure ..... am i correct in the way of thinking here ?

 

[albano]

..... am i correct in the way of thinking here ?

I don't claim to be a expert, BUT I would say you are thinking WRONG!...the pressure is from the height, not the volume. The rock 'displacement' does not change the pressure. Your waterline is low to have enough room for the additional water from the 75g surge tanks (which is also additional pressure). I was told, (many tanks ago) that 1/2" glass or acrylic could hold back the OCEAN...at a depth of 24" (not factoring in wave and tidal pressure)....in other words, you could have a million gallon tank made with 3/4" acrylic, as long as the depth (height, not front to back) is not over 30"

 

[camaroboy8691]

I don't claim to be a expert, BUT I would say you are thinking WRONG!...the pressure is from the height, not the volume. The rock 'displacement' does not change the pressure. Your waterline is low to have enough room for the additional water from the 75g surge tanks (which is also additional pressure). I was told, (many tanks ago) that 1/2" glass or acrylic could hold back the OCEAN...at a depth of 24" (not factoring in wave and tidal pressure)....in other words, you could have a million gallon tank made with 3/4" acrylic, as long as the depth (height, not front to back) is not over 30"

i belive you on the hight thing . im not sure about the pressure thing tho . i might have to do an expermiment before i setup the tank now . lol . might have to get a sensors to mount on the sides of the tank and then do a test with rock . and then without rock to see what kinda pressure is placed onto the glass . i really think that having something solid inside the tank taking up water volume would create less pressure on the sides than that of something with only water . but im not sure im only a metal fabricator not a engineer by any means .

also with this tank setup the 2 75gal surges would only make the water rise alittle bit at a time . the over flow on this tank is made to drain water extremely quick to move the water to the sump .

 

[sayn3ver]

quick search on the interwebz, i remembered bits a pieces from physics class in highschool but this does it better.

the pressure exerted by a static fluid depends only upon the depth of the fluid, the density of the fluid, and the acceleration of gravity.

The most remarkable thing about this expression is what it does not include. The fluid pressure at a given depth does not depend upon the total mass or total volume of the liquid

http://hyperphysics.phy-astr.gsu.edu/Hbase/pflu.html#fp

 

[sfsuphysics]

Well what you could do is buy it, chop the tank up panels in half, and have a monster octagon tank!

(ok just kidding.. most likely those panels are bowed a bit... however.... yeah its something I would do if it was super dirt cheap, like practically free cheap)

 

[Newby-Reefer]

I don't claim to be a expert, BUT I would say you are thinking WRONG!...the pressure is from the height, not the volume. The rock 'displacement' does not change the pressure. Your waterline is low to have enough room for the additional water from the 75g surge tanks (which is also additional pressure). I was told, (many tanks ago) that 1/2" glass or acrylic could hold back the OCEAN...at a depth of 24" (not factoring in wave and tidal pressure)....in other words, you could have a million gallon tank made with 3/4" acrylic, as long as the depth (height, not front to back) is not over 30"

I agree but you have to take into consideration of the length of the tank. a 4 foot tank is going to bow alot less than a 40 Foot tank.

 

[Pufferlips]

I too was looking at getting this tank till I received the pictures of it and the information on the thickness of it. Glad I passed

 

[Seasapience]

I've actually seen this tank in person, and those seams look stronger than most tanks I see on here, and what you're seeing is not bubbles, lol but where the wedges are melted in... Seems like all these "experts" would know this... Btw, 1" is fine for a tank this size. Actually this tank is made better than most manufacturer's standards. At $4500 I think it's a steal! Especially when you factor that a new tank of this size will cost about $9000-$12000, lol... I'd buy it in a heartbeat if I had the money...

 

[Seasapience]

I too was looking at getting this tank till I received the pictures of it and the information on the thickness of it. Glad I passed

Ironically, or coincidentally , there is another 1200g listed on ebay (Manufactured by Custom ATM Tank of Las Vegas) which is considered to be one of the best in the world (check out their work) and it's 5' tall and only 1 and 1/8" thick, lol... It's only $12,000 and it's even got a chip in it (they say from a nail gun). Came across this and remembered this thread and all the inaccuracies it had in it, so I felt everyone should see this

Here's the link;
http://cgi.ebay.com/ws/eBayISAPI.dl...Category=20755&_trkparms=algo=LVI&its=I&otn=1

 

[nguyentxd]

isn't all about the height of the tank that determines the thickness

 

[PaPa_Johnny]

I bet if everyone asked "Acrylics" (James) he would be of the same opinion as Troy and several others, this tank is an accident waiting to happen. Someone above said that the "craze" we are seeing in the pictures is not air, if it's not air it's definitely not a good bonding job. The seams on good acrylic work are transparent yes?

 

[Seasapience]

i.e. acrylic that is literally melted into place isn't completely transparent... you're not looking at a seam but rather where acrylic was literally melted into place, lol... As stated, I've seen this tank in person, and I think it was stated that you'd have to see it "in person" and since the guy that owns it isn't willing to ship, I think that is proof enough Btw, these pics look photoshopped from what I've seen in person.... Interesting what some people will do to make a buck on forum sites, lol... Funny thing is, I saw this tank relisted and the guy makes reference to this, lol...