# Lexan a good alternative ?



## Wind459 (May 2, 2007)

Im trying to make (eventully) a 100-150 gal tank. keeping my options open. I would rather stay away from glass if I could, Due to the fact of weight and bonding the corners. So plastics, I heard plexy glass is too weak, and can give off some sort of chemical in the tank. Acrylic is next, possibly the best thing I found so far, hard to find sheets of it though. Lexan is something a co-worker of mine thought might be good to use. I even considered plywood. What would be a the cheapest/strongest option to go? i was thinking of even going 2x2x5 149ish gallons.


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## dr2391 (Feb 11, 2009)

all *** heard of are glass, acrylic, and plywood. not sure what lexan is


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## Wind459 (May 2, 2007)

It is super strong material but way to expensive. It is used with bullet proof glass.
What is the easiest/best way for a novice to start out with ? I want to make a tank that is 2x2x2 ft.
What would be the easiest to work with /cheapest?


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## mithesaint (Oct 31, 2006)

I believe the cheapest way to get a 150 gallon tank is to buy one. It's hard to buy the raw materials cheaper than the manufacturers can get it, not to mention that DIYers tend to go overkill, which just makes it more expensive.

A plywood aquarium could potentially be cheaper, depending on how you sealed it. If you want to go acrylic or glass, you're probably better off buying one new.


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## under_control (Jan 9, 2008)

mithesaint said:


> I believe the cheapest way to get a 150 gallon tank is to buy one. It's hard to buy the raw materials cheaper than the manufacturers can get it, not to mention that DIYers tend to go overkill, which just makes it more expensive.
> 
> A plywood aquarium could potentially be cheaper, depending on how you sealed it. If you want to go acrylic or glass, you're probably better off buying one new.


Agreed. Look around on craigslist, and other classifieds. If you aren't in a hurry you will find a deal.

Look at new too. THe "parts" for making a tank don't seem to be cost effective until you hit about 200-300 gallons.


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## Mcdaphnia (Dec 16, 2003)

DIY is going to save money only with large and multiple tanks, if then. Plexiglass is acrylic, just a brand name, not a different plastic. However there are different ways of making acrylic and cell cast is preferred for an aquarium with any size.

Based on one seller's prices, you could get the panels for a 120 gallon Lexan tank for a little less than $600. Aluminum oxynitride (transparent aluminum) currently comes in sheet sizes limiting you to about 50 gallons maximum tank size but it would cost about $30,000.


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## Hoosier Tank (May 8, 2007)

You are using Brand Names and true names. 
Acrylic = Plexiglas 
Polycarbonate = Lexan



> Most people have no idea how many types of plastic there are. Literally thousands. The two we are interested in here are acrylic and polycarbonate.
> Acrylic is the generic term used to describe the clear hard material we all know as Plexiglas or Lucite. The chemical term is polymethylmetacrylate or PMMA for short. It was first introduced to the United States in 1930.
> Plexiglas is the brand name originally used by Rohm & Hauss, the early developers of this plastic type. Lucite is the brand name of DuPont's acrylic material. It's like Kleenex has become a term we use for tissue. I hear that in South America, Gillette is used for razor.
> Acrylic is the clearest of plastics, about 8 times clearer than glass. It has good strength but is breakable. Acrylic is fairly rigid, as plastics go but will flex much more than glass. Polycarbonate is even more flexible. Acrylic is a thermoplastic, meaning that it can be heated to a rubbery state and formed in various ways. It is the material of choice for museum cases and displays because of its clarity and workability. We can make glued seams that nearly disappear. We use acrylic almost exclusively for our products because of its workability and high quality. The exposed edges of acrylic may be polished to a clear finish. It can be bent like a sheet of paper by heating a line. Acrylic, as most plastics, will scratch if not cared for properly. That is probably its worst downfall.
> ...


.

Acrylic comes either "Extruded" or "Cell Cast". Extruded is weaker and does not have the impact resistance, structural strength of Cell Cast. Cell Cast Acrylic is widely used in the aquarium industry. Take a few minutes to read this Building an Acrylic Aquarium from our library's DIY section. :thumb:


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## BillD (May 17, 2005)

Lexan would be a poor choice for a tank as it is too flexibleand sags under it's own weight. Not sure if you can weld it like you can acrylic. My problem with acrylic tanks aside from the cost and scratchability is the bracing that is needed. It is a pain to work around.


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## mepeterser2451 (Mar 23, 2007)

if you've got the glass or acrylic for free then go ahead and build with what you got. otherwise, dont. plywood would be cheaper only if you've already got glass or can get glass cheap. thats what im doing this summer. gonna try to set it all up under 200-300 dollars. otherwise just go buy one.


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## parkayandbutter (Jan 15, 2008)

"Extruded is weaker and does not have the impact resistance, structural strength of Cell Cast. "

BUNCH OF Malarki............. Reasearch this info by calling the mfg of the actual product or even the product brochure............ "HELLO" rumors are spread. Facts ............ Get them from the source and stop playing "I KNOW everything"


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## Morpheus (Nov 12, 2008)

parkayandbutter said:


> BUNCH OF Malarki............. Reasearch this info by calling the mfg of the actual product or even the product brochure............ "HELLO" rumors are spread. Facts ............ Get them from the source and stop playing "I KNOW everything"


Not according to this website:

http://www.interstateplastics.com/detail.aspx?ID=ArtPlexiglass

Form the website:

There are two main processes in producing acrylic sheet. It can be extruded or cell cast. The extruded type simply means that a machine is pushing the liquified acrylic monomer between a series of rollers designed to flatten and cool the sheets as they run through the extrusion equipment. This most cost effective form of acrylic manufacturing is probably 80% or more of all the acrylic on the market. *The other manufacturing process is a cast acrylic. This form is made by pouring the liquid acrylic monomer between 2 sheets of highly polished glass sealed with a rubber gasket. This cell includes heat activated hardeners, or catalysts, and as the cells are gradually heated, typically through a series of water baths, produce a single sheet of solid acrylic. What you end up with is an acrylic sheet with little to no stress, and by virtue of the manufacturing process, is stronger due to the higher molecular structure of the sheet.* This more time consuming and expensive process is used mainly to manufacture thicker sheets or when the material is going to be used in an application where strength is an issue, such as aquariums or aircraft canopies, or when there is going to be some machining done to the acrylic. When you attempt to machine extruded acrylic the heat created from the machining tends to release any stress put in the material as the force of the rollers squeezed the material to make it thinner. You wont have this problem with cast acrylic since there was no stress introduced during the manufacturing process. However, one of the benefits of extruded vs. cast is that tighter thickness tolerences can be achieved during the extrusion process that in the casting process.


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## mepeterser2451 (Mar 23, 2007)

Morpheus said:


> parkayandbutter said:
> 
> 
> > BUNCH OF Malarki............. Reasearch this info by calling the mfg of the actual product or even the product brochure............ "HELLO" rumors are spread. Facts ............ Get them from the source and stop playing "I KNOW everything"
> ...


haha you told him morpheus. what an idiot. on this forum, parkayandbutter, people write what they know or believe , to help out others. Sure not everyones always right but you don't have to be rude about it. if you want to gain anyones respect then all you have to do is provide decent info that backs up your claim, just like morpheus did. if you think extruded is stronger than provide the info and dont make fun of morpheus.


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## mepeterser2451 (Mar 23, 2007)

here's some more evidence that extruded is weaker.

Monomer left in sheet can reduce the hardness, promote crazing when the sheet is fabricated, and in extreme cases lower physical properties such as tensile strength and modulus of elasticity

from this website
http://www.plasticsmag.com/features.asp ... Nov/Dec-00

also, what i always THOUGHT was wrong with extruded acrylic was it wasn't as clear as cell cast. it shows streaks.

"As an aside, monomer which is left in the molten resin can cause bubbles or streaks in the extrudate."
from the same website
http://www.plasticsmag.com/features.asp ... Nov/Dec-00


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## Mcdaphnia (Dec 16, 2003)

I remembered a Lexan tank that was in a pet shop that has been gone for years now. It was at least 200 gallons. It was four feet across in all directions (round) and three feet tall. If anyone bumped it, it would quiver like it was jello, but since it was a cylinder, it returned to its shape. The base was a circle of plywood which explains why it wasn't bigger. Instead of bonding the Lexan sheet to itself at the back of the tank, it was attached to a wooden riser. There are solvents that will bond Lexan but either they weren't available to the builder or he wanted the rigid riser for stability reasons and the fact it served to conceal the plumbing to the tank.


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## Hoosier Tank (May 8, 2007)

Thanks for coming to my defence guys.. when I posted the remarks I should have started with "*I believe *Extruded is weaker..." I try not to pose oppinions as fact, but regaurdless Cell Cast is what is widely used in the Aquarium Industry over extruded


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