I agree, I forgot to mention that we had placed water detectors under and had it not been for them ringing we would have woken up to wet floors and probabaly dead fish. There was no sign prior of water leaking above the tank nor drops of the floor. The way the stand and tank were made, I was able to look under with a flashlight and see the bottom of the tank, which we did every once in a while for 12 years. This week, I didn't check during my water change. Maybe a small drip would have been there, maybe not. Thank you again.
When is a tank too old?
- Thread starter fish2013
- Start date
A well built tank shouldn't leak spontaneously due to old age. There must be some structural defects that caused a tank to leak the first time such as micro crack in the glass or glue in between glass, glass panel too tall , too thin or of odd shape by design, or deformity caused by moving or unbalanced stand. Resealing only temporarily fix defects on the seam, rather superficial as majority of the silicone is between glass, and not correcting the fundamental deficiencies that caused leak in the first place.
Everyone I know of who has resealed tanks ended up having to reseal it again and again over months to several years apart. They all said to follow standard procedure including cleaning out old silicone and using industrial strength silicone. I may be painting a broad brush opinion based on my limited experience as everyone I know of could have followed the wrong procedure.
Hello; Such is the nature of experience. Sometimes I have resealed a tank and had to re do the job. I learned and got to the point of having tanks hold up for many years. A tenant of mine is we each get to run our tanks any way we want. I will try to reseal tanks most of the time. You can buy a new one as you wish. No problem other than making a "blanket statement" as you say.
Hello; Back in the 1950's and 1960's we had two choices. A tank with an angle iron metal frame or a tank with a stainless steel frame. both had a tar like sealant between the glass panels. Both tended to have a slate bottom. Time di a job on the angle iron frames, had some rust way. Stainless was the way to go if you had the money. I was 11 or 12 and had to mow lawns for a dollar, shine shoes for a quarter and other such chores. I bought the cheaper angle iron framed tanks.
I do have a survivor 40 gallon stainless tank in the basement sitting empty. Silicone has fixed the old tar sealant between the glass, but last time I set it up it leaked thru the slate. Must have micro cracks or some such.
No worries, I will ignore the tank sealing advice and carry on as is usual for me.
My first big tank was a used 55 gal stainless steel tank with slate bottom, very sturdy but heavy. Due to moisture accumulation on the metal hood, I got static electric shock touching the metal frame. I heard that you cannot keep salt water fish in metal framed tank.
My fish friend had an Oceanic 200 gal tank, made with thickest glass of comparable brand. The tank leaked at age 16 due to accidental breaking of the top glass brace. My friend replaced the top glass brace, and resealed the leak. It didn’t last, and he resealed the tank again and again a few months, a year, several years later and finally gave up. I heard similar failure stories from my fish club friends attempting to reseal big leaky tanks. It appears that once the structural integrity of the tank is compromised, it is not fixable permanently short of taking all glass panels apart and reglue as factory installation.
My fish friend had an Oceanic 200 gal tank, made with thickest glass of comparable brand. The tank leaked at age 16 due to accidental breaking of the top glass brace. My friend replaced the top glass brace, and resealed the leak. It didn’t last, and he resealed the tank again and again a few months, a year, several years later and finally gave up. I heard similar failure stories from my fish club friends attempting to reseal big leaky tanks. It appears that once the structural integrity of the tank is compromised, it is not fixable permanently short of taking all glass panels apart and reglue as factory installation.
I’ve never tried to seal a tank as luckily over the decades I’ve never had one leak(knock on wood). I will say that I’ve seen quite a few threads where it doesn’t work. This poor chap is a great example.
Hello; OK . I sense we are at the stage of being dug in on a point. A sort of "I am right" verbal fight. Again, you and others are entitled to run your tanks any way you please. You do not have to reseal a leaky tank. Buy a new one every time.
However, your stance flies in the face of mine and the experience of others. Many others. I moved into my current home in 2010 and got decent internet for the first time. I joined this site in the spring of 2011 with over 50 years fish keeping experience behind me. Soon enough a few 'forum experts" began telling me things i knew to be fine were not correct. Had I been a newcomer to the hobby I may have taken their advice to my detriment. But having kept tanks since 1959 I had learned the old-fashioned way about what works, including tank sealing.
I do not care if you never reseal a tank. Such is your choice. I do care that comments or advice which I know to be questionable not be left unchallenged. I get that a newcomer likely will not do a good job right away of resealing a tank. Took me a few tries. I was lucky/unlucky to not have the money to throw away equipment over a small leak.
Do what pleases you and i will do the same.
I tend to believe that the tank being supported on three points along the back likely was the likely contributor to the failure, especially if that cross piece in the middle was a smidge higher than one or both of the back corners. This could probably be remedied by adding a board under the entire back edge and some sort of compressible mat or dense foam between the tank and stand surface, should you decide to reuse the stand.
I went to my local pet store today and saw this 125 gal tall tank abandoned. I saw it set up as show tank 3 years ago, leaked spontaneously in 6 months, resealed and refilled again. I asked the store managed what happened. He said the tank leaked again despite multiple reseal attempts. It will not be refill for fish again but to keep reptile instead. It's a 4 ft, 24 in wide and tall tank.
Hello; While I get the point you try to make this post did not get it done. Guess you will fight on to try to make the point stick. Modify the stance a bit and get closer to the truth. That would be somewhere along the line of it can take multiple attempts to fix a leak and some folks give up.
Another tack might be some folks do not do the job the right way. Maybe they take short cuts or skip steps, I do not know.
Some folks like to try to seal without separating the glass panels which is my preferred method. Others try to separate the glass. I have simply gobbed silicone over cracks and stuck a cut glass pane over the cracks with success.
Last point this time around. Resealed tanks can leak again in time. A thing is so do never fooled with new tanks. If new tanks never leaked this conversation would be moot. A caveat being we are talking about intact tanks and not cracked or broken ones.
But I say again, we each get to run our tanks anyway we wish. Go ahead and discard or repurpose a leaky but intact tank as you will. I will most likely try for a reseal or two or three.
Have a dry day.
IMHO there is a big difference between re-building and re-sealing a tank. Either procedure is a PITA. Simple in theory, but tedious, time-consuming and wearisome in practice. Done correctly, the result is completely trustworthy and permanent. Done incorrectly...it isn't. And here's the catch: every inch of the total linear length of all the seams must be equally perfect. One bad spot, one imperfectly cleaned area, and the whole thing is a waste of time.
If it's an actual rebuild...where the glass panels are separated and then re-assembled...the same holds true, but it is literally two or three times as much work.
It's not a secret; it's very simple. Every square inch of glass that is contact with silicone must be absolutely clean, dry, oil-free and pristine. There must be no trace of old silicone left in place, and that's where most re-sealing jobs fall flat. New silicone will not adhere to old, cured silicone, so the old stuff must all be removed. Miserable, tedious work. "Good enough"...is not good enough.
A fellow for whom I worked building tanks almost a half-century ago was a little OCD, and so he was well-suited for this sort of obsessive attention to detail. He was such an artist with silicone that he would lay out the pieces of spotless, pre-cleaned glass on the tabletop, complete with jigs he built himself, in a room that was kept as clean and sterile as an operating theater. He would lay out a bead of silicone so precisely that when the glass was assembled, the amount that squeezed out of the seam was perfect for a quick finger wipe to create the internal sealing bead.
We mere mortals usually lay out a small bead that becomes the structural joint between pieces of glass, and then immediately after that apply a small bead around the entire internal seam length that is immediately smoothed into the sealing bead. This all has to be done fast, before any of the silicone begins to skin over.
Keep in mind that the structural bead is usually sufficient all by itself to create a strong, permanent water tight seal. The extra sealing bead is just a safety feature, in case there might be some tiny blip in the structural bead which doesn't put the assembly at risk of coming apart, but which might allow a slow leak.
So, if you have an older tank that has developed a slow leak, it's rarely necessary to re-build it. Strip off all the old internal seam...every last molecule of it...but leave the structural bead strictly alone. Replacing the internal bead will solve all your problems.
Oh, and the "old tank" thing? There must be a limit, but it's way, way higher than most seem to think. I know of at least three all-glass tanks...one of which I built myself, and the other two while assisting The Guru, that are over 50 years old and still holding water beautifully. Part of the reason is that back then, tanks were not made out of the thinnest glass imaginable; we used thicker stuff, which vastly increases the surface area and therefore the strength of the structural bead. 6-foot tanks were built with no cross-braces, and functioned perfectly. But the main ingredient is simply relentless, obsessive, unwavering attention to detail, mostly in cleaning.
By the way, those older thick-glass tanks were also better suited with their thicker structural seams to very slight imperfections in the stand. When you have a tank that suddenly, inexplicably begins to leak, the reason is often a stand that is not completely flat. Leaning a wee bit one way or the other is not the kiss of death many think it is, but if the tank is not completely and evenly supported all the way around...if it, for example, teeters a bit corner to corner...the stresses this sets up can be a tank-destroyer. Thinner glass tanks are more susceptible to this, and the cheaper-is-faster-is-better mentality that creates those tanks also contributes to stands that can just barely support the weight of the complete set-up, and which may very well be imperfect on the top edge.
Again...they don't build 'em the way they used to...
If it's an actual rebuild...where the glass panels are separated and then re-assembled...the same holds true, but it is literally two or three times as much work.
It's not a secret; it's very simple. Every square inch of glass that is contact with silicone must be absolutely clean, dry, oil-free and pristine. There must be no trace of old silicone left in place, and that's where most re-sealing jobs fall flat. New silicone will not adhere to old, cured silicone, so the old stuff must all be removed. Miserable, tedious work. "Good enough"...is not good enough.
A fellow for whom I worked building tanks almost a half-century ago was a little OCD, and so he was well-suited for this sort of obsessive attention to detail. He was such an artist with silicone that he would lay out the pieces of spotless, pre-cleaned glass on the tabletop, complete with jigs he built himself, in a room that was kept as clean and sterile as an operating theater. He would lay out a bead of silicone so precisely that when the glass was assembled, the amount that squeezed out of the seam was perfect for a quick finger wipe to create the internal sealing bead.
We mere mortals usually lay out a small bead that becomes the structural joint between pieces of glass, and then immediately after that apply a small bead around the entire internal seam length that is immediately smoothed into the sealing bead. This all has to be done fast, before any of the silicone begins to skin over.
Keep in mind that the structural bead is usually sufficient all by itself to create a strong, permanent water tight seal. The extra sealing bead is just a safety feature, in case there might be some tiny blip in the structural bead which doesn't put the assembly at risk of coming apart, but which might allow a slow leak.
So, if you have an older tank that has developed a slow leak, it's rarely necessary to re-build it. Strip off all the old internal seam...every last molecule of it...but leave the structural bead strictly alone. Replacing the internal bead will solve all your problems.
Oh, and the "old tank" thing? There must be a limit, but it's way, way higher than most seem to think. I know of at least three all-glass tanks...one of which I built myself, and the other two while assisting The Guru, that are over 50 years old and still holding water beautifully. Part of the reason is that back then, tanks were not made out of the thinnest glass imaginable; we used thicker stuff, which vastly increases the surface area and therefore the strength of the structural bead. 6-foot tanks were built with no cross-braces, and functioned perfectly. But the main ingredient is simply relentless, obsessive, unwavering attention to detail, mostly in cleaning.
By the way, those older thick-glass tanks were also better suited with their thicker structural seams to very slight imperfections in the stand. When you have a tank that suddenly, inexplicably begins to leak, the reason is often a stand that is not completely flat. Leaning a wee bit one way or the other is not the kiss of death many think it is, but if the tank is not completely and evenly supported all the way around...if it, for example, teeters a bit corner to corner...the stresses this sets up can be a tank-destroyer. Thinner glass tanks are more susceptible to this, and the cheaper-is-faster-is-better mentality that creates those tanks also contributes to stands that can just barely support the weight of the complete set-up, and which may very well be imperfect on the top edge.
Again...they don't build 'em the way they used to...
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