Will the 180 gallon tank I built leak/break once I fill it?

[sgossett9]

Thank you for your website. It is the only one I could find of it's type.

Here's the situation I'm currently in...

I purchased a 180 gallon glass tank (72Lx24Wx24H), 1/2" thick glass, which leaked because the silicon cracked along the bottom length. Using a razorblade I removed all of the silicon and disassembled the tank. I cleaned the glass with alcohol after virtually all the silicon was removed.

The building process: I placed the bottom glass on the basement floor with no spacer. I taped the sides up around the bottom piece. (You know how the bottom piece should be flush up against all of the sides? It wasn't. When the sides were placed around the bottom piece, there was a 1/2" gap between the bottom piece and the lengths. In other words the bottom piece was the appropriate length for the tank, but it was about 1" shy on the width.) After the sides were taped into place around the bottom base, and the gap between the two length pieces was even (about .5") I laid a bead of silicon on all of the inside edges. I used an extra thick bead on the length sides where the gaps were. After it dried, I flipped the tank over and filled those gaps on the bottom with silicon. Later I glued the support glass across the top.

My concerns: The tank sits on an iron stand, it doesn't have plastic frames on the top or bottom, the bottom surface of glass is flush with the bottom edges of the tank, and there's gaps along each bottom length of the tank which are filled with silicon and have extra thick silicon beads inside the tank. ALL GLASS WAS PUT TOGETHER, THEN THE SILICON WAS APPLIED AS AN INNER BEAD, SILICON WASN'T PUT ON THE GLASS EDGES BEFORE SETTING THE PIECES TOGETHER. I'm concerned that if I fill it the seam along the bottom length will rip and it will pour water.

Questions: If I put Styrofoam between the tank and the iron stand will that be sufficient to fill the tank and would I be confident it wouldn't leak? If not, what do I have to do to make this tank work?

I've been an aquarium enthusiast my whole life. I'm a 23 year old University of Michigan Dearborn student whose among the top of my class. I tutor business and math classes. My point is that you're talking to someone who can figure things out well. I've successfully built a 30 gallon. I'm not confident in this tank because when I bought it I attempted a fast fix by cutting out the ripped seal, cleaning the glass, and laying fresh silicon down just along the ripped area, which overlapped the old silicon in the corners. That resulted in severe leaking days after.

I need your advice because this 180 has sat in my living room, appearing to be built for over a month due to my reluctance to fill. My 8 red belly, and 3 gold piranhas are squished in a 30 gallon and have been for months, resulting in about 3 cannibalism casualties thus far.

You're Experience, and Honesty in helping a fellow hobbyist is appreciated man!

Scott Gossett
Canton Michigan

 

[redneckgearhead]

Wow. Yea if you have a gap between your glass and no frame I would be very leary of it (even with a frame) your glass should fit flush and tight against each other. And Ive never seen a tank that size with no frame I would be very hesitant. If your tank is a common size you can order frames for it. AND no do not use styrofoam or padding under a glass tank.

 

[ccCapt]

Exactly what brand/type silicone did you use?
I would not fill it. Silicone is not structural and won't provide any strength where there is no glass (a gap). There should also be a thin layer of silicone between the pieces of glass, not glass against glass.

 

[Todd2]

ALL GLASS WAS PUT TOGETHER, THEN THE SILICON WAS APPLIED AS AN INNER BEAD, SILICON WASN'T PUT ON THE GLASS EDGES BEFORE SETTING THE PIECES TOGETHER.

Tanks are not built this way. The inside seam acts as a sealant not an adhesive. The tank will leak before it's even full.

Sorry to rain on your parade, but I would sell/scrap the tank and look for a used one on craigs list. Even if you disassemble the tank and re-silicone everything the edges of the glass will not be 100% clean. It's near impossible to scrape every bit of silicone off and have that sucker 100% clean. Silicone sticks to glass, not old bits of silicone. It may look clean and feel clean, but there's microscopic bits you can't see still there. You're playing russian roulette here. 180g on the floor is not a puddle, it's $ in water damages.

If you're **** bent on doing this you NEED to talk to a tank manufacturer or someone who builds tanks for a living. But I'd strongly advise against going forward here.

Here is a REAL good thread on reef central discussing tanks, glass thickness, bracing, silicone etc. It gets a little into engineering, but it's very informative.

 

[Sicklid]

Is it possible that you could have put the sides together incorrectly? Not saying that your stupid, I'm just wondering if the tank was designed to have an even gap all the way around, and it would have worked out that way if you had overlapped the lengths over the shorts sides, instead of the short sides overlapping the edges the front and back panels. I've illustrated it to explain what I mean...

 

[Aqua-fan]

This isn't real help - it's just preventative help.
I recently bought a 38G tank off Craigslist that looked like it had seen better days. The bottom frame was broken at 2 corners and effectively useless. Then I read that those plastic frames are just to hold the tank firm while the silicon dries in manufacture. The frame serves only a decorative function. To put my mind at ease about filling this tank - I took the following precaution. -
I set a piece of old plywood on the ground in my backyard. I then put a wrought iron stand on top the plywood (so the legs wouldn't sink into the yard.) I put another piece of plywood over the top of the wrought iron stand and set my 38G tank on that. Then I filled it up with 4" of water and looked for any leaks. After about 10 minutes, I filled it the rest of the way up and let it set overnight. Happily it held water just fine, no leaks whatsoever, and if it had broke or leaked it would have only watered my lawn, not my living room
The tank now sits in my living room looking good and I'm confident in its 'structure'.

 

[Crepe]

This isn't real help - it's just preventative help.
I recently bought a 38G tank off Craigslist that looked like it had seen better days. The bottom frame was broken at 2 corners and effectively useless. Then I read that those plastic frames are just to hold the tank firm while the silicon dries in manufacture. The frame serves only a decorative function. To put my mind at ease about filling this tank - I took the following precaution. -
I set a piece of old plywood on the ground in my backyard. I then put a wrought iron stand on top the plywood (so the legs wouldn't sink into the yard.) I put another piece of plywood over the top of the wrought iron stand and set my 38G tank on that. Then I filled it up with 4" of water and looked for any leaks. After about 10 minutes, I filled it the rest of the way up and let it set overnight. Happily it held water just fine, no leaks whatsoever, and if it had broke or leaked it would have only watered my lawn, not my living room
The tank now sits in my living room looking good and I'm confident in its 'structure'.

You seem to fail to realize this is 180 gallons of water, not a measily 48 gallons.

180 gallons of water will weight about 900 pounds. Then he will have to add about 200 pounds of sand on top of that. I would not risk it.

Secondly you don't seem to understand the nature of the problem. The actual class is NOT set correctly. The edges are not flush meaning that the silicone would be providing the structural support, a job that should be done by cross braces and top braces.

And finally, the "rims" you see on a tank do indeed provide support. The larger your aquarium the more important it is to have those supports to keep the silicone from ripping apart. The silicone is a sealant, the braces hold the glass together so less pressure is applied to the silicone, preventing a failure.

We were providing help in the form of forewarning of a terrible catastrophe waiting to happen. Would you rather spend 400 dollars on another aquarium or 2000 on mold control, carpet replacement, wood replacement, and hours of headache cleaning up AND a new aquarium including livestock.

 

[ShawnMMcKenna]

Actually, 180 gallons wieghs 1,530 pounds. Thats alot of pressure pushing against the tank walls....I believe the tank would fail at about 40% full.

 

[Aqua-fan]

In response to Crepe's post

Crepe;
I'm sorry if I offended your advanced knowledge with my post. You apparently know better than most. When you use words such as 'fail to realize' and 'measly' - then I assume you are well, looking down your nose. You know, a little knowledge can be a dangerous thing. 1173 posts does not make you an expert on anything. You failed to read my entire post or you wouldn't have ranted on about 'mold control', carpet replacement, etc. You need to slow down a bit, perhaps.

You stated 'We were providing help . . ."
Funny I don't see any other post of 'yours' in this thread.

I'll also have to keep in mind now that 180 gallons only weighs 900 lbs, as you state. I didn't know that, I thought it was 8.34 lbs. per gallon. Live and learn, I guess.

Finally you say the 'rims' provide support to keep the silicone from ripping apart. Are you sure? That's some tough plastic then, isn't it? Another 'live and learn'.
Chill out Crepe. I was just relating my experience - not comparing it to yours

 

[Crepe]

Sorry for being so reactionary. Oh and I did a slight miscalculation, I was thinking 108 gallons, not 180 gallons. Furthermore, cloaking vicious remark in flimsy sarcasm doesn't make a post any less inflammatory. Flame baiting is against TOS, I'll ignore it though. I was trying to prevent someone from making a bad choice due to incorrect advice.

YES you do need cross braces and top braces in a large tank. I don't know where you're hearing that you don't.

Your pointing out that my calculations were incorrect actually further bolsters my point that it would be most prudent to find another tank or get the glass properly cut/set.

And finally, strawman fallacies are no substitute for substantive discussion or rebuttal.

 

[Aqua-fan]

Crepe

Flame baiting you'll ignore??
Your miscalculations 'bolsters your point' ??
'strawman fallacies' ??

You gotta' be kidding me.
Some people can simply never be wrong.

I don't want to get so far off topic here so let's let it go, shall we? I'm sure readers aren't interested in your or my 'misunderstandings'.

One correction. I never said cross braces and top braces didn't support a large tank. I was referring to the 'decorative' plastic perimeters.
As I suggested, it would be better to fill the tank 'outdoors' than indoors, in case of a spill. That's all there was to it.

 

[Sicklid]

Not trying to aggravate the wound, but those plastic perimeters are well more than "decorative." They keep the tank together, albeit in conjunction with the silicone...

If you look closely at most tanks, the glass DOES NOT TOUCH on the vertical seams. There is actually a 1/8th inch bead of silicone in between the panels. This is how they are built, and the silicone does indeed provide structural integrity. That stuff is VERY strong, but not strong enough to last without the top, bottom and side bracing on a large tank....

 

[Aqua-fan]

Ok, let's see if we're on the same page here.
My original reference to the plastic tank frame (and it's alleged supporting role), was for my 38G tank. My bottom frame was broke. After I filled the tank 'outdoors' and left it for a day (without the broken frame) I found no problems. Once I leveled the tank on a nice solid base indoors and filled the tank, I took black electrical tape and ran it around the base of the tank, for it's decorative effect.
Here is an actual 180G tank.

The top framing is quite extensive and certainly needed - but is the bottom framing piece? If the concensus here is that you can't operate without the bottom frame, then I'll certainly go along with that.

My whole original post was merely to suggest filling the 180G tank outdoors if the OP was leery of it leaking.

 

[Greenmaster]

The building process: I placed the bottom glass on the basement floor with no spacer. I taped the sides up around the bottom piece. (You know how the bottom piece should be flush up against all of the sides? It wasn't. When the sides were placed around the bottom piece, there was a 1/2" gap between the bottom piece and the lengths. In other words the bottom piece was the appropriate length for the tank, but it was about 1" shy on the width.) After the sides were taped into place around the bottom base, and the gap between the two length pieces was even (about .5") I laid a bead of silicon on all of the inside edges. I used an extra thick bead on the length sides where the gaps were. After it dried, I flipped the tank over and filled those gaps on the bottom with silicon. Later I glued the support glass across the top.

I believe that you need to disassemble your tank. There should have been 1/8-1/4" gaps that shouldn't have been gaps they should have been filled with silicone. It sounds to me like you took the aquarium apart and then put it back together differently. It is possible that the sides of the tank get placed on top of the bottom slab instead of around, and the gaps were probably about the thickness of the glass. I don't know if you took pictures of the glass when you took it apart but I would suggest taking the tank apart and then doing a little more research prior to putting it back together. One important thing to note is that no glass should be put directly on glass. There should always be a layer of silicone between them. There are some good clamps out there to help you do perfect 90 degree corners and hold them till they are dry. A tank should be built in stages and not all in one sitting. But you should be certain how it all goes together prior to applying glue.

My concerns: The tank sits on an iron stand, it doesn't have plastic frames on the top or bottom, the bottom surface of glass is flush with the bottom edges of the tank, and there's gaps along each bottom length of the tank which are filled with silicon and have extra thick silicon beads inside the tank. ALL GLASS WAS PUT TOGETHER, THEN THE SILICON WAS APPLIED AS AN INNER BEAD, SILICON WASN'T PUT ON THE GLASS EDGES BEFORE SETTING THE PIECES TOGETHER. I'm concerned that if I fill it the seam along the bottom length will rip and it will pour water.

The plastic frame from most of the tanks I have seen (including my 320g) are there to cover up the unsightly silicone edges as well as protect the silicone. They don't add to the strength of the tank, but they add to the aesthetics and possibly the longevity of the tank.
The biggest concerns here are that you didn't build the tank the same way as it was originally built, and you didn't silicone the glass edges before setting the pieces together. Silicone is not exceptionally strong, the strength is in its bonding power. The surface to surface with a thin amount of silicone between is where most of your strength is. The interior bead of silicone is to ensure that there are no minor leaks and to help protect the structural part of the silicone. On some larger tanks (like mine) they have an extra piece of glass about 1/4"x1/2" that they glue to the bottom/sides of the tank for that extra holding power.

Questions: If I put Styrofoam between the tank and the iron stand will that be sufficient to fill the tank and would I be confident it wouldn't leak? If not, what do I have to do to make this tank work?

No the Styrofoam will not be sufficient... although once you have "rebuilt" the tank then Styrofoam is good.
I am confident it will leak.
To make the tank work you need to do a complete tare down and rebuild I would invest in some corner clamps ($20-$80 depending on what you want) and either ask for step by step instructions or do some research and find some step by step instructions.

I hope that I have been a little more help then the bickering that has been going on... most of the people on here want to help and are not as concerned on "flaming"

Welcome to AA and I hope you enjoy the time you spend here.

 

[jcarlilesiu]

YES you do need cross braces and top braces in a large tank. I don't know where you're hearing that you don't.

Not necessarily. My 150 gallon has no bracing.

 

[BillD]

There is a lot of misinformation being diseminated here. So much so, I'm not sure where to begin. I can't understand how this tank existed with the bottom half an inch narrower than the side spacing, unless it was incorrectly assembled, as shown in the drawing in a previous post.
Large tanks don't need plastic trim to hold them together (nor do small tanks). Most really large tanks dont have any trim along the bottom.
A tank should be assembled in one operation, not in stages as suggested. If built in stages, you are pretty much guaranteed to have voids, which are places for leaks to materialize. A properly assembled tank will not leak even without the inner fillet seam.
Whether a tank needs any bracing depends on the thickness of the glass. If thick enough, no bracing is needed. Sometimes the braces are added to facilitate adding glass tops, rather than for reinforcing.
The plastic frames most commercial tanks are built with (the one piece ones) are to facilitate the assembly, and lift the bottom off any solid stand. If the glass bottom were to sit on a single grain of gravel it would break when filled. or even before. This was soon discovered by the originators of the all glass aquarium. They added a frame to raise the bottom to avoid this.
All glass aquariums do not have a 1/8" space between the panes on the butt joints that hold the tank together.
Angle clamps are not needed to assemble a tank. Tape will work, although if you are concerned, small 90 degree angle brackets can be used if you want, along with plastic clamps.
Contrary to what was also stated, styro is essential under a tank with no trim to lift the bottom. A tank with the bottom supported is stronger than one that is suspended. The stand takes the bottom pane out of the equation as far as strength goes. It also make the bottom less likely to break if something falls on it, such as a rock. If the glass can't flex, because it is fully supported, it is unlikely to break.
Getting back to the original question, a tank can be built with sides flush with the bottom, although my preference is for the sides to sit on the bottom.

 

[Bige]

I aggree with billd. He hit the nail on the head. Having said that, I would rebuild and be certain it is right.
Aquarium Fish Tank Build Aquariums

Here is some info. There is also a video but I couldnt find it. Pm me if you want more info. I have built several tanks from sheets of glass.

 

[jcarlilesiu]

YES you do need cross braces and top braces in a large tank. I don't know where you're hearing that you don't.

I have a 150 gallon all glass tank that is braceless from the factory.

Also.. I believe that the person you are arguing with was simply saying that the tank should be tested outside to see if it fails.

I thought this was common knowledge and sound practice when rehabbing a tank. Why your initial reaction to his post?

As for the OP. Sealant is not made to span gaps, but rather provide a water tight seal as previously stated. If during reassembly, you have spaces in the tank at the bottom, then I have to assume that you assembled it back incorrectly. The attached PDF by another poster is a good example of the potential error. I wouldn't risk it, but testing it outside on the lawn probably isn't a bad idea.

 

[BillD]

One thing needs to be mentioned about setting up a tank outside for testing. the same care needs to be employed as if it were set up inside. That is to say, the tank needs to be well supported on a level, flat stand. To do otherwise is to invite failure, or cause strains that may result in failure later.