Anything wrong with an 'older' tank?

[Vmax911]

I'm looking at buying a used tank that is about 8 years old. Is there anything I should be concerned about? It is currently in use, so I know it holds water. Is there any life expectancy data on aquariums?

 

[shayfish]

If its not leaking and not majoyly scratched/still looks good there's no reason I can think of why you shouldn't use it.

 

[trotty]

IMO i would be concerned with age.... glass can become brittle ova time and silicone, although not subjucted to heat or direct sunlight will and can let go over time. 8 years is not alot but could be enough, and your still yet to move it. Just my 2 cents.

 

[Burks]

My dad and I revived a 21+ year old tank (it's older than I am, it was his before I was born) this spring/summer. Replaced all the silicon seals and the tank has been running just fine for nearly four months.

Just make sure there are no small cracks in the glass. Just give it a really good look over and replace the silicon seals. It's better to spend $5-$8 on silicon then replacing all the fish, the tank, and cleaning up the spill if the seals break.

 

[jsoong]

My tank is 10+ years old (Oceanic) and I think it is better than some of the newer tanks - for one it has 3/8" glass rather than 1/4" commonly seen in the newer tanks so I don't have bowing & other structural problems.

It is true that the silicone seals will age & fail, but 8 yr is not that long (silicone generally have 15-30 year life span). To be sure, check that the silicone is still supple & not starting to peel off the glass. It is pretty easy to replace the seals if needed (took me a couple hours & $5).

As long as the glass is not too scratched up, I say go for it.

 

[Zagz]

I would say if it appears to be in good condition go for it. I inherited 2 15 gal tanks that are 30+ years old and had to reseal one of them. I filled them up with water on the deck and let them sit for a couple of days to check for leaks. They have been running for me for a year now.

 

[Toirtis]

I would say if it appears to be in good condition go for it. I inherited 2 15 gal tanks that are 30+ years old and had to reseal one of them. I filled them up with water on the deck and let them sit for a couple of days to check for leaks. They have been running for me for a year now.

Agreed....two of my currently running tanks are pushing 50.

 

[justrelax]

glass can become brittle ova time

I have never heard this before... Not that I don't believe it, but does anyone have anything to back this up? I too have a 20+ year old tank and, while I thoroughly checked the silicone, it never occured to me the glass could be "brittle".

 

[MyCatsDrool]

Glass is actually a liquid. it does not become brittle.

 

[justrelax]

Glass is actually a liquid

This got me thinking, so I did some research.

Glass
From Wikipedia, the free encyclopedia
Glass is a uniform amorphous solid material, usually produced when the viscous molten material cools very rapidly to below its glass transition temperature, without sufficient time for a regular crystal lattice to form. The most familiar form of glass is the silica-based material used for windows, containers and decorative objects.

In its pure form glass is a transparent, strong, hard-wearing, essentially inert, and biologically inactive material that can be formed with very smooth and impervious surfaces. Glass is, however, brittle and will break into sharp shards. These properties can be modified or changed with the addition of other compounds or heat treatment.

Common glass contains about 70-72 weight % of silicon dioxide (SiO2). The major raw material is sand (or "quartz sand") that contains almost 100% of crystalline silica in the form of quartz. Even though it is an almost pure quartz, still it may contain a little (<1%) of iron oxides that would color the glass, so this sand is usually enriched in the factory to reduce the iron oxide amount to <0.05%. Large natural single crystals of quartz are purer silcon dioxide, and they, upon crushing, are used for the high quality specialty glasses. At last, synthetic amorphous silica (practically 100% pure) is the raw material for the most expensive specialty glasses.

Glass as a liquid
One common misconception is that glass is a super-cooled liquid of practically infinite viscosity at room temperature and as such flows, though very slowly, similar to pitch. Glass is generally treated as an amorphous solid rather than a liquid, though different views can be justified since characterizing glass as either 'solid' or 'liquid' is not an entirely straightforward matter [1]. However, the notion that glass flows to an appreciable extent over extended periods of time is not supported by empirical evidence or theoretical analysis.

A myth does exist that glass rods and tubes can bend under their own weight over time. To check it, in the 1920s, Robert John Rayleigh, son of the nobel prize winner John William Rayleigh, conducted an experiment on a 1 meter (39 in) long, 5 millimetre (~3/16 in) thick glass rod, which was supported horizontally on two pins with a 300 gram (0.66 lb) weight in the middle. Apart from the initial bending of 28 millimetre (1.1 in), the position of the weight didn't change until the end of the experiment, which lasted for 7 years. At the same time, another man, a worker of General Electric named K. D. Spenser, conducted a similar experiment independently. Two months after Rayleigh, he published his own results which also disproved the myth. Spenser suggested that the myth was composed before the 1920s, when the tubes were made by hand, and naturally some of them were curved to begin with. Over time the straight tubes were taken away, and only the curved ones remained. Some people probably thought it was the glass flowing.

 

[Thaiboxer]

I re-sealed an older 125 gallon a couple of years ago and it's worked fine. I concur with everyone else on the scratches though - they get really annoying. Now that I've got a little more money I'm going out to replace the 125 with a scratchless (new) tank.