What's the life expectancy on a giant acrylic tank?

Orthopod

Dovii
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Feb 22, 2010
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I have a chance to pick up a 10'by4'by2' tank that is 1/2 inch acrylic and 15 years old. I was wondering what the life expectancy on the tank was.

Anyone have an idea?

Thx.
 
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wednesday13

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May need some going over... all my acrylic tanks are 20-30yrs old and run just fine with a bit of tlc if needed. some things to look for are "dry spots" (white areas) in the seams where they may be pulling apart and crazing. dry spots can be reglued in weld on #3 or #4 and if u cant get to them that way...u can reinforce the inside seams with bevels of weld on #40. all depends what it looks like tho. some minor repairs are no big deal in my book... give it a good inspection before u buy... if u find problem areas use that to get a better price.
 

vincentwugwg

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I have a chance to pick up a 10'by4'by2' tank that is 1/2 inch acrylic and 15 years old. I was wondering what the life expectancy on the tank was.

Anyone have an idea?

Thx.
Really depends on a few things.. I have a tank that is over 22 years old (10ftx6ftx2.5ft)and it still looks like it's new.. then I also have tanks that were build for me 2 years ago(6ftx2.5ftx2.5ft) and already look crappy. Most important thing for you to do before buying the tank is: Check seams(make sure they are intact) and condition of panels.
I feel that those are the most important things to check at this moment.
 

Lepisosteus

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If an acrylic tank is properly maintained and cared for you can expect to have it until you no longer want it. Look at the seams, air bubbles and crazing. As for the acrylic itself nothing you can see as long as it's not cracked it's fine
 

Orthopod

Dovii
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Feb 22, 2010
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I appreciate the responses.

Another question from the answers, what is the definition of "crazing" in reference to acrylic tanks?

May need some going over... all my acrylic tanks are 20-30yrs old and run just fine with a bit of tlc if needed. some things to look for are "dry spots" (white areas) in the seams where they may be pulling apart and crazing. dry spots can be reglued in weld on #3 or #4 and if u cant get to them that way...u can reinforce the inside seams with bevels of weld on #40. all depends what it looks like tho. some minor repairs are no big deal in my book... give it a good inspection before u buy... if u find problem areas use that to get a better price.
 

aldiaz33

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Jun 19, 2007
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There is no universal answer to your question because there are too many variables. However, in my experience longevity depends on a few things:
1. The skill of the builder- ex- an inexperienced builder may need to force the acrylic with clampes (i.e.- bend it) to make contact when solvent welding the seams...this will be a point of stress and where the tank will first show signs of stress and eventual failure.
2. The brand of acrylic used- not all acrylic is created equal. The better known tank builders will use quality cell cast acrylic whereas the fly-by-night guy may take shortcuts and use cheap (or even extruded) acrylic to save some money/make more profit. Brand name tanks are almost always safer than a DIYer or a less reputable builder.
3. The thickness of acrylic used- tanks made of thinner material will show more signs of stress along the seams due to deflection/bowing whereas tanks made of thicker material will have stronger seams and less stress placed on seams because there will be less deflection/bowing.
4. The treatment of the tank- ex- placed on a level stand with full support underneath, not exposed to extreme temps, never dropped, etc.

As others have mentioned, you want to look for clarity in the seam. If the seams are foggy/cloudy, show signs of excessive crazing (from the inside to the outside of the seam) or a lot of bubbles, the seam will not be as strong as if it were completely clear. The frustrating part is that you never really know when it will give. There is a LFS near me that has a 3' tall display tank that has the most horrendous looking seam I've ever seen (bubbles, crazing, cloudiness...everything you don't want to see) and it has been holding water for many years, but man I wouldn't be able to sleep at night if that tank were in my living room. I would pay good money for used tanks from reputable builders where the seams still appear to be in good shape; in my opinion a well built tank can last 30+ years.
 

Orthopod

Dovii
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Feb 22, 2010
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Thanks for the reply - I will try to get a picture of the seams and post it.

The tank is from a DIYer and not name brand.
 
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