Outside nick/leaking aquarium 5/8/08
Hi, I have an old 90 gallon freshwater aquarium. There is a small nick on an outside corner of the tank and the water is very slowly leaking out of it in small beads.
<Oh! Not good.>
I have resealed the tank on the inside, but the tiny leak is persisting. I guess the nick must extend to the silicone seal inside.
<Yes.>
Is such a nick in the corner glass irreparable, or might I have just resealed it incorrectly on the inside?
<At the very least you will need to actually cut out all the silicone inside the tank, scraping and cleaning all the silicone off the glass for a new, continuous bead run inside. Ideally you should take the entire tank apart, remove all the silicone (even replace the chipped panel) and reassemble with new silicone throughout. For the time and effort involved you may find it more cost effective to buy a new tank. You just have to consider how much your time is worth to you.>
Anything you can tell me would be very helpful, thanks!
Forest
<Welcome and good luck, Scott V.>

 

Glass Tank Repair 5/3/08 I bought a new (still has store stickers on it) 125 gal tank yesterday at the Goodwill. After I got it home I noticed it had a chip on the inside of the front panel that reminds of a windshield rock chip. It is 1/4" x 1/4" oval shape and is 1/16th" deep. The tank is 6 feet long and the chip is 7 inches from the bottom and 29 inches from the side. Is this repairable, and if so how? <May be fine as it is. How thick is the glass? James (Salty Dog)> Re: Glass Tank Repair 5/9/08 It is 3/8" thick <I'd feel comfortable using the tank with that glass thickness, no need to repair. James (Salty Dog)>

 

Question about a Chip in my Tank 4/15/08 Hello, <Hi there Kevan.> My wife and I just recently bought a new 72 Gallon Bow Front tank and stand. <Awesome, congratulations!> We are new to the hobby so we wanted some input on a possible chip on the top corner of our new tank. The tank has been filled now for over 24 hours without a single leak or problem. <A good sign.> As I was looking at the tank this afternoon, I saw what first appeared to be a bubble. Upon looking at it further, I could feel the chip in the glass right beneath my finger nail. Now, it’s very small, hasn’t gotten any bigger and it’s located about 3 inches from the very top of the tank so there isn’t much pressure on it from the water. <There could not be a better spot to have a chip.> I’ve attached some pictures of this as a reference. Your expert opinion on whether this would compromise the structural integrity of the tank would be appreciated. Thank you! <It is so small that it’s difficult to make out in the pictures. From that and your description I will say all is fine with the tank. > Ps – my LFS said they didn’t think this was a problem at all considering its size and location. They thought it would be more of a cosmetic issue over anything else. <Agreed.> Kevan M. Farley <Best regards, Scott V.> Re: Question about a Chip in my Tank 4/16/08 Scott, one more quick question. <OK> I noticed you cropped the pictures I sent, but it doesn't show the chip that I found on the tank. The chip is about an inch or so below the tape you see on the tank. Just want to make sure you were looking at the same thing. Thanks! <Oh yes. I still have the originals in my download box, we are looking at the same thing. The pics get cropped for reasons of format and download speed for others. No worries, your tank is fine.><<RMF apologizes for the mis-crop>>

Cracked 150 4/12/08
Hi Crew,
I have to start off by saying what a great site! You have helped me in so many ways as I have only been in the saltwater hobby for about 4 months.
<Hello, it is good to hear the site has helped you so much!>
I have a problem. I purchased a 150 gallon tall tank being 72"x18.5"x 29" used. I took it to my LFS and had it torn apart and resealed. I waited a week before filling it to make sure the sealants had cured. During that time I constructed my stand. I used 4x4 post one in each corner and then I used 2x6 yellow pine #2 doubled up for the front middle and rear beams. I used a single 2x6 for the sides and used Simpson hangers to help support the beams. Next I put a layer of 3/4 plywood that I liquid nailed and screwed to the top. Everything was screwed together and I feel I may have been a little screw happy but better safe than sorry!
<Yes, for certain. The structure of the stand sounds fine.>
I cut the carpet so the stand would be in direct contact with the slab.
<Even better.>
I test filled my tank and all seemed to be ok. So I went for my permanent installation. I had custom cabinets built to make this look like the tank is in the wall.
<Nice.>
I did put a double layer of underlayment foam under the tank. This is the same foam underneath wood floors. The tank is drilled with one overflow box in the left corner. Also the tank has a middle glass support at the top. The tank has been up and running since December 23 of 2007. Now for my problem. I recently checked to make sure my tank was still level and that the stand had not compressed or settled in any bad ways. Well I was horrified to find out my tank was leaning to the back, 1/16" on the right side and 1/8" on the left!! Left to right was level still however. I quickly asked multiple LFS if this was a problem. Only one said to drain it and put foam under the tank. Before I could get home to drain it, you guessed it, it had a six inch crack on the left side in the middle stretching out to the center.
<Yikes, not good.>
Luckily no water had started to leak. I quickly called my neighbor who has a 125 gallon and we drained the tank and saved all coral, live rock and fish.
<Great!>
I am about to pick up a brand new 150 tall but am worried about what I did wrong. I don’t want to come home to a flooded house. What should I do? Will foam take care of the fact that the stand settled 1/16 and 1/8?
<You are better off shimming between the stand and slab to level things out, with a continuous piece between the shims and the stand. It is possible the slab settled somewhat. However, I do also suspect the stand is no longer planar, likely more than 1/8” off to crack the tank. With the foam you already had underneath it the 1/8” is just what showed. You will need to put the stand in place, shim it level and then check to make sure the top is planar. A simple level/straight edge can tell you much here. Slight variations can be accommodated with Styrofoam, a ½-3/4” thick piece. If the stand is too far out of whack you will need to either remake it or look into alternative leveling techniques, such as epoxies.>
Please advise before I resume my project. Thanks again for all the help!
PB
<Welcome, a few pertinent links below. Good luck, Scott V.>
http://www.wetwebmedia.com/aqstdleveling.htm
http://www.wetwebmedia.com/aqstdfloors.htm

Chipped Corner 3/31/08 Hi, first time writing to WWM. <Hello, welcome to WWM.> I got an aquarium yesterday, 36x24x24 marine. <Nice shaped tank.> Apparently, one of the edges was chipped in shipping. It's not like the other chips you had pictured on the site so I thought I'd write in with a picture. <Good pictures.> I was told to just seal it with an epoxy like you would on a car windscreen, so I did. But, now that I've read your site, I'm a bit worried. As you can see from the picture (2098), the glass of the bottom panel is chipped on the edge, but it doesn't extend very far in except at one point. <Looks like nothing to worry about in this picture.> Also, it appears that there is still a layer of glass in the panel that is intact above where the glass chipped out. I've since sealed this with an epoxy in hopes that it would strengthen the joint and it would be ok (picture 2106). <This picture appears to show a little more destruction, but still nothing I would worry about.> No, the glass isn't that scratched up, its just dirty and it shows under the flash :-) <The story of photographing glass, and through it too!> What's your opinion? If this was an ordinary tank, I wouldn't be too fussed to try to replace the bottom panel, but it was drilled out for me and everything and includes a weir that's firmly attached which would pose a problem. <I think all is fine here as far as using the tank. Consider contacting the manufacturer/shipper regarding the damage. It is likely too late to do anything about it, but I assume you did not buy a damaged tank! Best regards, Scott V.>

Chipped Tank 3/19/08
Hello WWM crew!
<Hello.>
I have an Oceanic 58 glass aquarium that my wife got for free when she worked at Petsmart. Problem is, it has a chip at the corner that extends all the way into the silicone (The little piece of glass is still there).
<Not good.>
I filled it with water outside and let it sit for a few days, and it did not leak. I would really like to turn this into a display tank, rather than just relegate it to my basement fish room. If I silicone a couple pieces of ¼ glass to the corner in order to cover up the chip, will this function to keep the water where it is supposed to be (not all over my floors)? Or do I have to replace the entire panel? I know it's better to replace the panel, but I'm cheap and if I don't have to then all the better!
<The patch will work to keep the water in place and reinforce the damaged area. If you price a pane of glass you will likely find it is not too terribly expensive to replace the whole pane. It is just a lot of work!>
Thank you!
<Welcome, good luck, Scott V.>

Used Tank, Chip/Scratches/Recaulk 3/1/08 Hi guys & gals - <Hello Jim.> I recently obtained a 280gal used tank, and I'd like to think that I got a great deal on it, but there's a few things keeping me up at night: <OK> 1. There is a large chip in one corner about halfway up. Using a Dremel tool I ground it out to remove all cracks, but the resulting divot is large, being about 3/4" long and about half the width of the glass pane (see attached pics). After looking over similar posts on your website, and since the chip is not anywhere near the seam, I think this is safe - would you agree? <In this case, yes, I think this is fine.> 2. The bottom glass pane has a dense network of scratches. Apparently the previous occupant was a 3 foot gator, and I imagine he scratched up the bottom while pawing at the sand. Since I want the tank 100% filled with water for fish, is there a danger that the scratches will weaken the tank? None of the scratches are deep and I am sure they aren't cracks. <I wouldn’t worry about this.> 3. Since the silicone caulking was damaged in some spots, I decided to scrape it all out and recaulk the whole inside of tank. I followed the advice on this website: http://www.aquarticles.com/articles/management/cannon_usedtank.html (this was before I found your excellent web page). I was careful to scrape out all the old stuff and clean it out well with alcohol before recaulking. After 4 days drying I refilled the tank and it has held water for two days now. But here is my concern: the original caulk was about 1/4" at the corner, but the stuff I put in was only 1/16"-1/8" deep. I've heard that "less is more" with this kind of job, but I can't help worrying when I see that every other tank out there seems to have thicker caulking than mine. Am I running the risk of leaking in the future? <No, not really.> Should I redo it with thicker caulk while it's still in my garage? <I would not, it sounds like you did a nice job. The real structure of the tank comes from the silicone directly between the panes of glass. The excess globbed into the corners is just for extra leak prevention. It is a good idea, but not wholly necessary. What you have sounds fine.> Thanks for any help you can offer -Jim <You are welcome Jim, all sounds and looks OK here. Have fun, Scott V.>

Glass Tank Damage 2/18/08 Hello Crew! <Hello Elizabeth.> First, I'd like to take this opportunity to thank you all so very much for making available such a wealth of knowledge to plebes such as myself through your marvelous website... <Welcome, it is a pleasure to take part in and thank you for the kind words.> I am sorry to bother you on a holiday, but I've encountered a bit of a  problem in moving my 220 gal tank and would be so thankful if you could point me in the right direction. <OK> I've skimmed the FAQ and have come to the conclusion that this *may *not be as big of a problem as I first suspected, but again, allow me to put this to you to decide. Whilst moving said tank it happened to find itself on a collision course with an unsuspecting countertop. <Uh-Oh.> The result? A chip on the bottom corner/edge of the tank I lack a camera to provide you with a picture, I have included a small diagram which will hopefully help a little. ( Also, I find a suitable similarity to picture #2 for the FAQ *Tank Edge Chips 12/7/07* only the chip is singular and larger). Now, the glass is tempered (if that makes any difference) The chip itself is approximately 1/3 up the height of the tank and a far as I can see it was a clean break, the chip is loose but not lost and I can't seem to see any cracks that came from the impact. Seeing as it's such a large tank, my concern is that the structural integrity of the tank might be compromised based on the location of this chip or its presence at all. <Me too.> I am having trouble telling myself this is something I can turn a blind eye to without checking in with you folks first. <This falls into the “test outside, in a safe place” category.> So is this damage negligible? <It does not appear to be. From your diagram (I may be seeing it wrong) it appears the chip is through the entire silicone seam.> Is there anything I can or should to structurally support it? Fix it? <I would just replace the pane of glass if the silicone bond in the area is lost. It is a lot of work to replace a pane, but it is cheap compared to a tank bursting, not to mention dangerous. And the tempered glass will do just that if it fails, burst and not crack. Otherwise, do test it outside for a few days, if the glass is tempered it is likely structurally fine.> Thank you very much for all your time and everything you do. And a happy presidents day to all of you. -Elizabeth <Welcome and you have a good holiday also. By the way, nicely done diagram. Best of luck, Scott V.>

Another Pit In Glass Question 2/1/08 Dear WWM Staff, Wow, I stumbled upon this site the other day and have been fascinated by all the information available regarding tank repair! Very impressive. <Thank you, the site has many years of combined experience and input.> Like others, I was hoping you give me some much needed advice/direction, at the same time possibly easing my mind a little. As recommended, I first searched WWM for questions/advice <Thank you.> relating to a tiny pit in the glass and found 3 related entries, but after reading through them I was a little unclear about a few of the suggestions made by WWM. I was hoping you could provide a little more clarification, based on my situation. In my case, the tiny pit I found was probably made by a rock bumping into the glass wall at some point in time. For reference purposes, I have a 110 gallon, 48" x 18" x 30" glass aquarium which is about 1-1/2 years old. Pit is located approximately 12" from one end and 13" from bottom. Currently, the tank is only filled about 24" high because it is used for aquatic turtles so figure around 70 gallons of actual water, however, in the event I do use this for fish one day, I guess I'd also like to know how it would fare if filled close to its capacity. I have included several photos but I'm not sure whether they give the illusion the size and depth of the pit is smaller or bigger than it actually is. I found the following FAQs: (1) In aqrepairfaqs.htm, "Aquarium Repair - 55 gallon" the person described having a "small chip on the INSIDE of the long front glass... about 1/2 way down and front and center" to which WWM Steven Pro suggested to give the tank a test fill somewhere easy to clean up, like on the porch or garage before bringing it inside. My question is, how long should I let the water sit before I can conclude that the tank is safe? <As far as integrity to hold water, just filling it will do, maybe let it sit for a few hours.> If a pit will cause a failure, will this be exhibited rather quickly after filling, or could it take weeks or longer? <It should be evident quickly, over time if the chip were to grow. You have nothing to worry about in your case.> As an alternative, Steven suggested discarding the tank and buying a new one but if this 110 gallon tank is salvageable, I'd rather not have to go that route. (2) In glsaqcracks.htm, "Chips in tank 5/28/06" the person described having multiple chips/nicks the size of a ball-point pen tip, which is about the size of my pit (I have included a few photos). Bob Fenner replied "likely no problem" so I'm wondering, given my tank dimensions, whether my pit should be a concern. <No.> (3) In glstkscratches.htm, "Small chip in 75 gal – 06/14/07" the writer describes a "very small (pinhole size) chip on the center of the outside front glass" yet this time Bob Fenner replied there could be a little to worry about and "...if it bothered me much, I'd return and exchange this tank," <Yes, it appears he was referring to aesthetics.> and when asked if there was anything he could do to fill it in so it couldn't be seen, Mr. Fenner replied "Could try, or have it ground down." Could you provide more specifics regarding what could be used to fill it, and is filling it an option if the pit is on the inside surface rather than outside? <Filling it will still leave some distortion, grinding down as mentioned in Bob’s response is an option if you wish to repair. > I also saw the reference to DIY'er grinding a pit using a Dremel, but would this be an option for me considering the location of my pit? <I wouldn’t, it will likely look worse.> Would smoothing it out decrease the chance of failure, or would it be more for cosmetic reasons? <Cosmetic.> Is this sort of thing costly to have done professionally (my tank is dry right now so I could even lug it to a shop to have done rather than have them pay me a visit)? <I don’t imagine it could cost too much, call and shop around.> Finally, how is a tiny pit different from say, a scratch, as far as the integrity of the glass is concerned? <There is very little difference unless either is fairly severe/deep.> As a last resort, can a small plate of glass, say 4" square (or however large you suggest?), be siliconed on top of the pit on the inside face to maintain structural integrity? <No need for this.> In my case, I can always reverse the tank so that what's currently the front face can easily become the back, so if adhering a glass plate would do the trick, then that might not be so bad. If this is feasible, where would I apply the silicone, would I fill the pit with silicone and then along the perimeter of the glass piece, press it to the aquarium, and then seal along the edges, or should the silicone be spread evenly across the entire face of the glass plate being applied? Thanks for your time, I really appreciate it. Wonderful site! <Very welcome. You have nothing to worry about, just flip the tank around and enjoy the view through the other pane. Your chip is very minor. Thank you for such a clear well written email on a subject you obviously researched first and the great pictures you included. Best regards, Scott V.>

Chip Out of Fish Tank Corner 1/8/08
Hi, I just purchased a used 75 gallon fish tank and noticed that the top plastic trim is cracked in the upper right corner.
I also noticed that a small chip has been gouged out of the corner of the tank itself. It does not look like the glass has any cracks in it.
<Good.>
Just rather that maybe when it was stored, something bumped into it.
<Fairly common and likely.>
It is in the very front right corner, so it appears that the glass is now thinner in this area of the corner. Does this weaken the glass?
<Technically, yes. But, if the chip is fairly small and there are no cracks coming off it you will be fine.>
Will it cause the tank strength to be lessened and not be able to hold the water when I fill it?
<It shouldn’t leak so long as the silicone seal is not affected by the chip.>
If so, is there any type of filler that can be used to this area that might help it?
<I wouldn’t worry about filling it in.>
Please help?
<If you have concerns of the tank leaking, fill it outside and test it for a few days. Minor chips on the corners of tanks are common and generally no big deal. It is when the chip is deep in the pane of glass, effects the silicone seal, or radiates small crack(s) that the chips cause concern. You can contact the manufacturer of the tank and order a new top trim if you like. The damage you describe to the trim can be fixed with a plastic epoxy if you want. You can usually find it with the glues at most hardware stores.>
Thanks so much!!!!
Bobbie
<Welcome, good luck, Scott V.>

Chip Out of Fish Tank Corner 1/9/08
HI! I just got your response, thanks so much, Very Helpful!!!
<Great! Happy to help out.>
The chip is about the size of a dime and kind of deep. Almost like half the width of the glass. Do you think that will still be OK?
<Likely could be, a chip like you describe can be ok. Be sure there are absolutely no cracks, not even small almost undetectable cracks, radiating from the chip.>
I have not paid for the tank in full yet and it is out of state. I won’t be able to test it for another month or so. I'm afraid to pay for the entire tank unless I have a better idea whether or not it will hold. If it has affected the silicone seal and that is all. Am I able to just remove the one side of silicone and re-caulk it? Or does the entire seal of the tank need to get removed and then re-sealed?
<This depends, if there is a large gap between the two panes due to the chip, I wouldn’t personally even try to fix it. If it is leaking for some reason, I would cut out the entire inner seal and apply new silicone. New silicone does not adhere well at all to previously cured silicone.>
Also, the top trim that is cracked. This top trim doesn’t have anything to do with the strength of the top of the tank, right. It is just a cosmetic piece?
<For the most part it is. Some tanks do use a plastic cross brace integrated into the trim to help minimize deflection (bowing) of the glass. If this is the case you may want to consider a repair or replacement.>
Thanks!!!
<Welcome and good luck, Scott V.>

Small Chip  12/23/07
Hello,
<Sean>
I have purchased a used Red Sea Max aquarium and have noticed a very small chip on the outside back panel of the glass. As the max has an overflow, this chip is on the overflow panel rather than the main aquarium panel. It appears to be a surface nick (less than 1/2" wide and just few mm deep). Since the overflow only holds 5 gallons of water I was wondering if I need to be worried about this chip and if so, if I should try and repair ?
Thanks!
Sean
<I would not likely be concerned here... re the size and type/place of this chip. Bob Fenner>

Tank Edge Chips 12/7/07 Here are some pics of the 90 gallon I picked up for a $100. It's going to be used for a quarantine and hospital tank. I was in a rush and didn't realize some of the glass and molding <had chips>. Will this hold up? I have had water in for 24 hours and no problem but wanted your take on it. Sorry about all the emails lately. <No problem.> 1st pic is a molding crack the rest are glass oyster cuts but no cracks. I did my best to crop and fit for WWM sorry if it's not great. (Bob my apologies I know you work very hard to make it all readable for the rest of the readers, and my apologies to the rest of crew if this didn't turn out to be best email sent. I did try my best before sending.) So will this hold up for a couple years for a quarantine/Hospital tank? It's even predrilled for easy access and for a $100 and no scratches on front glass I fig what the heck. Thanks again guys/girls. Don V. <The cracks in the frame/trim are of no consequence. The chips on the outer edge would not concern me since there are no cracks running off them. The main concern will be the chips along the silicone seam. How deep are they through the seam? It is hard to tell from the pictures. As long as most the seam is tact you should be fine with this purchase. Welcome, Scott V.>   90 Gallon Glass And Molding Question…Chips In The Tank’s Edge – 12/09/07 Eric, <<Hey Don>> I had sent this an email with new pics, might of got lost or you guys are swamped as always so I'll resend. <<Okay mate>> Think this tank will hold up? <<Hmm…it’s difficult to be certain from the pics as I’m sure you understand, but I agree with ScottV’s earlier assessment re…as long as the seal is intact, it doesn’t look like the small edge chips should be an issue. But…I would recommend filling this tank “outside” and letting it set for a day or two and check for any leaks/failure of the seal>> Thanks again to you and all crew members for putting up with us citizens! :) <<No worries my friend…is what we do! [grin] Eric Russell>> Re: Tank Edge Chips 12/9/07 See if these are better, thanks. <These are easier to see what is going on. This tank may hold (you have had water in it), but some of those chips appear to be fairly severe. The two large chips above the thermometer concern me the most, along with the two large chips on the other seam. Not only are these large, but three of them appear to be where the panes are bonded with the silicone. I may use it as a mixing tank outside or even possibly as a sump with a lower water level, but I would not be comfortable putting it in my house. Welcome, good luck, Scott V.> Re: Tank edge chips 12/10/07 Hey Scott, Thank you for the reply another question though if you don't mind, do you think I can get it fixed? <Possibly, I wouldn’t.> Or fix it myself with some silicone or buying a glass to brace it so to say? <You could put a strip of glass on the seam to help, but I am not confident that it will. The thin layer of silicone between panes is structural, effectively making this a structural defect. I will put this in Eric’s box for any input here.> Thank you for your hard work and time. <Welcome, good luck, Scott V.> Re: Tank edge chips 12/10/07 – Eric’s input... Hey Scott, Thank you for the reply another question though if you don't mind, do you think I can get it fixed? <Possibly, I wouldn’t.> Or fix it myself with some silicone or buying a glass to brace it so to say? <You could put a strip of glass on the seam to help, but I am not confident that it will. The thin layer of silicone between panes is structural, effectively making this a structural defect. I will put this in Eric’s box for any input here.> Thank you for your hard work and time. <Welcome, good luck, Scott V.> <<Hi Don, Eric here... I understand and agree with Scott’s hesitancy to recommend a “fix” for this tank. Without laying eyes on the tank, we can only advise on the side of caution. You may well be able to fashion a patch, but we can’t/won’t guarantee it will make this tank safe for use. If you do decide to try to effect a repair, I would affix with silicone two-inch wide strips of glass the full height of the tank (use the same glass “thickness” as that of the tank glass) on each angle of the "outside" corner creating a double-layer/laminated effect....extending one strip just past the edge and abutting the other strip up to it (with silicone betwixt), and positioning this joint “opposite” that of the tank joint. In other words, use these strips to create a corner joint just like that of the tank, but with the “seams” in opposing positions. Also, what is your intended use for this damaged tank? Even with this “patch,” I would likely relegate this tank to sump-duty where it would typically only hold about half its normal volume...and then, not without filling/testing in a safe place outdoors for a week. Abundans cautela non nocet... Regards, Eric Russell>> Re: Tank edge chips 12/11/07 I returned it for a brand new 75 gallon thanks for the advice Don V. <Great, much safer. That will be quite the quarantine tank, if that is still your plan. You're welcome, have fun, Scott V.>

Mmm, makes RMF uncomfortable.

Chip outside new 72G glass tank  10/15/07
Hello,
I just finished setting up my new 72G glass tank (bow face) and, after the first night, I noticed a small chip on the outside right at the intersection of the bow with the right side of the tank. Could it just be the result of "settling"? There is no leak and it appears that it's a surface chip. Question: should I ignore it, or should I replace? Note: the tank is pretty level - might be a bit off on the opposite side of where the chip is (meaning to level it perfectly, would require a small raising of the opposite end of the tank from the chip)- which leads me to think that the chip is not the result of the leveling.
Thanks in advance,
Tejas
<Greetings. Glass chips not so much because of "settling" as from careless transportation. The fact that the tank isn't precisely level almost certainly doesn't have any bearing on the chip you can see. An aquarium should be as level as you can possibly make it though. But slight deviations don't matter too much. Glass is strong but brittle, so while it resists the static force of water very well, if it bumps into something hard, it cracks or chips. Conchoidal fractures (chips that look like scallop shells) are very typical of glass being struck against something like stone or metal. As for whether this is a problem: if you're looking for a guarantee that everything will be fine, I can't provide one. Glass aquaria are only predictable when they are in perfect condition. As soon as they are damaged, the explosive forces of the static weight of water can concentrate on that single "weak spot", and the chances of failure increase. You might be lucky, and the chip will cause no problems. But you might not be lucky, and a year from now the tank will suddenly crack open in the middle of the night. If you can, and it isn't too expensive to do so, consider replacing the tank. The "cracked" tank would be perfectly useful for someone keeping reptiles or small mammals, so you might well be able to sell it on, reducing your losses. Alternatively, remove the cracked pane of glass and install a new one (there are instructions on repairing tanks at: http://www.wetwebmedia.com/aqrepairfaqs.htm and elsewhere. Hope this helps, Neale>

Cracked freshwater tank – 10/9/07
I have a 45 gal. long with a crack on the bottom. it is about 14 in. long and goes from one wall to the other going caddy-corner. I got it from a friend who had before me and he sealed it with 2 plates of 5/8" in. thick glass with silicone between the plates and the tank. before setup I took all the trim (except the plates. couldn't get them off) and resealed it and the crack with silicone. it sprung a leak at the bottom of the tank on the face at the joint. just a pinhole.
sealed it once more and let it set for 48 hours. I got the leak down to a slow drip, but would like it to stop. I don't have money to buy a new tank but I have 3 tubes of all purpose silicone that is waterproof with mold deterrent (sorry for the spelling). what should I do and how can I get the plates off to do a full fix instead of fixing around it. thank you for your time.
Andrew
<Andrew, I sympathise! I was in the same situation a few months ago. Personally, I'm not one for repairing tanks because of the potential damage that can be caused if you make a mistake. Check to see if your tank is covered in your home insurance as well, in which case replacing the tank won't cost you anything at all. Anyway, there's a whole slew of articles on repairing tanks in the 'Aquarium Repairs' section of this page: http://www.wetwebmedia.com/marine/maintenance/index.htm . Cheers, Neale>

Question, chipped glass tank    7/17/07
Hello WWM,
I was just given a 100 gal aquarium that has 2 chips in the corners. They are sea shell shaped chips that slightly touch the silicon, which I'm sure is not good. I have read several of the other questions you have answered from people who have similar situations. From reading those responses I am convinced that the tank can fail because of the chips. My question is:
Would it prevent the tank from breaking on that corner if I reinforced it with something like a PVC elbow and 100% silicon on the inside and the outside?
<No or at least very minimally...>
I am planning on building this tank into the wall so the chipped edge would be unseen, it can be ugly as long as it works. You guys usually tell people who have had similar questions to "give it a try", which I am willing to do.
<I am not so cavalier in general... I would at the least Silicone a length of glass (of at least two inches width, over the outside and chipped areas... the height of the panel>
I guess I would like to know if you have ever done anything like this and had it work or is there a better way. Of course, if the tank blows up on me I won't get mad at you guys, I just appreciate the advice.
If it would help I could send some photos. Thanks for your help.
Craig
<There are extreme possible dangers in such a "blowing up"... Consider the suggested repair/band-aid. Bob Fenner>

New 260 litres with corner chip and crack  7/12/07
Greetings from Canada. Great site! I've been reading your site since I got my 20g :)
Recently I bought a new Hagen Fluval Osaka 260 tank with stand at closing LFS. During transport I noticed left corner at the back of the tank has small chip (frameless tank with aluminum brace covering front and sides panels). Good thing the small glass grains didn't cut my palm. Looks like that corner got struck before and I didn't see that in that under lighting LFS.
Once I setup it up in my basement I noticed there is a small crack 2" length at the back panel close to that corner but doesn't extend to joint. No leak so far for 3 days now and the crack is not growing. It appears to be growing from inside glass to outside but haven't reach outside. I will double check if the crack is inside the tank (not only inside the glass).

| |
| |
left | /
|__________
bottom
(view from front)

Since it's final sale I contacted Hagen for warranty and still waiting for a response. Meanwhile what should I do?
<Lower the water level half or more...>
I plan to move in few months so should I plan to patch that crack and test before I move?
<I would, yes>
If I go with the patch, should I patch inside or outside or both (I prefer outside since it's easier)?
<The outside... with a strip/panel of glass... as/at I see below where you've been reading>
I read all Aquarium Repair FAQs and I would rather not go with replacing back panel is possible.
Many thanks!
Norick
<Welcome! Bob Fenner>
 

Chipped tank  7/8/07 Hi, I bought a 65 gallon tank today. It was in someone's apartment on the 5th floor of the complex. I had it in a shopping cart to easily move it around. When taking it out of the elevator, the wheel on the cart got stuck in the door track and the door closed on my tank. It chipped at the corner of the tank on the edge of the pane of glass. I'm including some pics. I feel it's in decent shape to use, but my dad thinks otherwise. Was hoping you could take a look and assess the situation. <I see this...> In the last two pics, you can see the edge of the glass panel it's siliconed to and how deep the chip is. Thanks, -Josh <Mmm, the position (lower) and one "spidering" of this break worry me. I would really like to see you apply a thin (maybe two inch wide) piece of glass over both sides of this broken corner... the height of the tank... perhaps overlapping, or beveled... to prevent failure... 100% Silicone... Most any thickness of glass will do... double-strength is sufficient. Bob Fenner> Re: chipped tank– 7/10/07 Hi Bob, Do you think using Plexiglas instead of glass for the repair would work ? -Josh <No>

Cracked Aquarium Bargain! – 06/14/07
After spending an hour and a half skimming through your site trying to find an answer to my question, I found conflicting answers, so I decided to email you to get a final ruling.
<Interesting. I typed "repair" into the search box on the first page, and came up with whole bunch of pages on aquarium repairs, such as this... http://www.wetwebmedia.com/aqrepairfaqs.htm >
> There is an aquarium on craigslist for 75 dollars that I was thinking of buying. It's a 75 gallon rectangle tank, stand, lights, and filter. The catch is there is a crack on the bottom of the tank (See picture). Now, I know that it is very expensive to get the glass replaced and much more worth it to buy a new tank. However, someone said to me that she had the same problem, put a new piece of glass on top of the old piece, sealed it, and it has held fine. All in all, it cost her 36 dollars to do her 40 gallon tank like that. Is this something you would advise?
> Thank you!
<If you're good with DIY and are willing to take a gamble, sure, it's worth a shot. Worst case, you get a decent set of hardware and simply replace the tank with a new one. But if you do try repairing a tank, read up all the tricks first, take your time, clean the tank thoroughly, take appropriate safety measures, get a friend to help, and DO THE JOB SOMEWHERE WATERPROOF so you can check for leaks. Ideally, work outdoors if its nice and dry where you are. Me, I'd by the set-up, take the tank to the recycling depot (for the glass), and then go buy a nice new 75 gallon tank. Cheers, Neale>

Re: banded bamboo shark... in a tank that went kaplooee! – 5/25/07
Thanks for your reply unfortunately since I mailed you ,what was a small crack at the top of my tank has shot down from one corner of the tank to the middle and back up to the other corner!
<Yeeikes!>
I could hardly believe my eyes.
There (naturally!) was gallons of water all over the carpet and the fish have all been moved to my 180l quarantine tank. Thought this was worth telling you guys incase anyone else out there like me thinks a little crack is not a threat. A CRACKED TANK IS ALWAYS A BROKEN TANK! Thank you for letting me air my stress!
Cheers, Andrew.
<Hope all dries, but not the livestock... hope they all survive! BobF>

Chip in tank  5/15/07 Greetings, <Likewise!> I got a deal on a pair of 55g tanks, and while getting them in the door, I chipped the corner of one of them. <Oops.> Attached is a picture of the chip. The chip itself is shaped like a seashell half with a bump at the edge tapering to razor thin at the edges and is towards the bottom of the tank. <Technically, a conchoidal fracture, which means precisely what you said, "like a seashell"!> How serious is this, can it be reinforced without replacing the whole panel? <Potentially quite serious, because it is a definite weakening on the glass.> I think these are older tanks, and have no center bracing if that makes a difference. <A 55 gallon tank holds a lot of water, over 200 kilos of the stuff, and I wouldn't trust that panel not to break under the force. Perhaps you can donate or sell to someone keeping a snake or lizard? Replacing the panel is an option of course, but hard work with a tank that size and (obviously) has to be done properly and carefully.> Thanks Paul <Cheers, Neale>

Crack in glass tank…   4/1/07
Hey guys, you seem like the authorities
<Well Bob hasn’t given me my badge yet or a/my M-16, hehe.>
Hi, do you know anything about aquarium repair?
<Anything? Yes…>
  We just brought a 3 by one  foot tank home and it cracked at the bottom edge.
<Just bought? Is return possible?>
Its about a two inch  crack near the bottom that extends to the very bottom corner in the silicon sealing region.
<That’s not good.>
  The top part is a hairline crack that may not even leak, but is at the edge of the sealant,
<That worries me.>
it then veers out into the pane before coming back and ending in the bottom corner where its cracked all the way through, also touching the silicon.  Is there any way to patch from the inside, scraping the old silicone away and using a small piece of glass on the inside and possibly even the outside?
<No if it is a true “crack” and not just a chip…the tank silicone would have to removed, the entire tank disassembled, the broken glass plane replaced…the silicone would have to be redone and allowed to cure.  I wouldn’t take chances with a crack in the glass and the living room floor, the crack will spread and weaken the tank overtime.>
  Or make a right angled piece of  glass on the outside around the cracked area completely sealed.  Will that absorb the pressure.
<No.>
  Or should I replace the whole panel and scrape and reseal the whole tank, which I really don't want to.
<If not this…the only choice is a new tank.>
Is there any chance just a patch would work, even if you absolutely coated the repair piece with silicon?
<Unfortunately no, this wouldn’t be reliable.>
Cheers,
Eric
<Adam J.>

Question about crack in the tank   03/07/06
Greetings, my name is Murphy and I have a question about a crack in the back panel of my 35 gallon glass tank. The problem, prior to the crack, was a small insidious leak from th back of a threaded bulkhead in the upper right-hand corner of my tank. I went ahead and attempted to tighten the bulkhead up even more to see whether that would alleviate the leak. Well, needless to say I tightened a wee bit too much and ended up with a crack going from where the glass had been cut out to make room for the bulkhead up to the top of the tank. Now, I went ahead and applied silicone aquarium sealant to both the inside and outside surfaces of the crack. though I should mention the crack seems to have not breeched the outside of the tank and just stayed inside, and you can see the crack taper up to the point where it meet the hole that was cut out for the bulkhead. I'm in dire need of advice. can I get by with just the sealant, or is this going to either A) necessitate the purchasing of a new tank or B) replacing the back panel of the tank all together.
Considering that the crack is small and it's at the top of the back panel, i figured it wont be exposed to much water pressure whatsoever. And also, again, it appears to have not gone all the way through to the other side of the glass, but i understand better safe than sorry.
<It is probably best to just replace the aquarium...on a tank so small and inexpensive it would be more costly and more of a hassle to replace the pane of glass. The sealant may work but what happens if you are not home/on vacation and it breaks? It's better to be safe than sorry. You wouldn't want 35 gallons of water all over your living room floor. Good luck, IanB>
sincerely and with beaucoup thanks,
Murphy Conn Griffin

New aquarium cracked/shipped - 2/5/06
Hey! I bought a new, second hand, fish tank to day, quite large about1m long 30cm wide and 40cm tall (for £10!!!!),
<sounds like a good deal>
but as I was getting it in my house I clipped it on my garden wall and it has taken quite a big chip out of the corner and a crack is running about 6cm down it.
<Oh no!>
Is there a way i can repair it (because I cant afford a new tank!!)
The chip might've been OK, but the crack sounds far too dodgy... Only option likely left is to replace the side panel(s) with new glass. Depending on the glass shops you approach, it may be cheaper/easier to hunt around on message boards or auction sites for another tank.>
If you could help that would be great!
Thanks Robyn
<Best regards,  John>

Chips in tank   5/28/06
Hello,
<Mornin'>
I have spent some considerable time trying to locate an answer to my question, with no luck so far.  I had recently acquired a used 75 gallon aquarium.  Since it is about 5 or so years of age, the scratches on the tank did not concern me.  There is a chip on the outside edge of the tank, but the glass is very thick and it looks only to be a surface nick.  Do I need to be concerned about that?
<Maybe yes/no... Less so if "near the top", not deep/large...>
As far as I can see, it's not near the silicone.  The tank has been set up for about 2 weeks now, with fish and plants in it for the last week and a half.  While maintaining the tank today, I noticed some chips/nicks on the inside of the tank walls.  I'm not sure if they were there when I first acquired the tank or if they somehow recently appeared (though I wouldn't know how).  I am using a Coralife lighting system with full spectrum lights for the plants, which can cause the water to get hotter, even though the lights come with fans.  I have also installed another fan which is helping to circulate the air under the canopy and keep the water temp down, but the temperature of the water is still
slightly over what the heater is set at.
It varies around 80-81 degrees (which I have been told by a fish "expert" that that is no cause of concern; although it did get to 82 degrees today, but not sure if that is influenced by the room temp being at 81-82, not yet using the AC).
<This should be fine>
Anyway, the chips/nicks are very small, the biggest one no larger than the pinpoint of a pen and they are in the middle of the glass, not anywhere near the silicon sealant; there are a handful or so on the same panel though very small in size.    Should I be concerned about these chips?
<Seems like you are... but likely no problem>
I don't want to come home to a carpet full of water and dead fish/plants, so it has me a little worried.  Any suggestions as to how I can seal or fix the chips, apart from buying a new tank (which is something I would prefer not to do, especially since the glass of this tank is very thick).  Thank you for any help you can provide!
Michella
<Mmm, some glass can be "filled"... some shallow pitting can be "ground down"... but these are very likely cost-prohibitive (more than a new tank). If the tank is fine thus far, it will likely continue to be. Bob Fenner>

Overflow Crack ?  12/20/06
Greetings WWM. Am very excited to be mailing the gods of aquaria.
<"Always thought I'd be an apostle/disciple"... in my best Superstar voice...>
Lots of info here - please let me know your feelings ...
<It's very pleasant, warm down here visiting in FLA... and I'd really like a cool beer... oh, that's not what you were hoping for>
thanks. Got a reef ready for fresh water Glasscages 55x23x28 inside-water = 150 net gal with a modified, (w/lotsa work), 45 gal "pre-made" Glasscages acrylic sump to a wet-dry. Did my homework, it's been three months of work, used sched 80, silicone and glue in all the right places. It is on the main floor, 3/4 in. Brazilian mahogany, over a weight bearing wall, finished basement below - usa homeowners insurance no coverage (unless vandals/fire/nature).? Any recommend?
<Mmm, call your agent here re coverage itself>
Used double felt on floor under oversized 5/8 in. plywood foot under modified, (w/lotsa work), wood cabinet carefully leveled/flat with linoleum, (felt allows easy sliding everything without water-nice).
<Good tip>
Used 3/4 in. pink foam (as per Glasscages 90 day warr) and linoleum between stand and tank, to make flat/level. The tank, (very Euro braced), is very flat/level all four sides, with or without water, as measured on the top plastic trim and/or glass. Top of water to inside bottom of Euro glass is 1 1/8 in. all four corners. Have two center-end, three-side 7x10x29 in. overflows with two 1 1/2 + 1 in. bulkheads ea.
<Mmm, wish these were larger inside diameter... even if fewer in number>
Tank glass is 1/2 in, overflows and Euro brace surrounding the bottoms of overflows, etc is 3/8 in. Used 1 1/2 in deep half in. Mex Beach grey-black pea gravel - beautiful.? Is it ok?
<For?>
Have had water in it for two months. Ultimately did the fish free cycle thing with 2-5 ppm ammonia (Ace Janitor Ammonia - comes @ 10% strength) 1 tbs at a time until nitrate spike.
<Mmm, such exogenous ammonia can be made to be of use...>
Took three weeks and worked great. Three ppm ammonia vanishes in two days now. Am planning to get all the fish together from the distributor in one visit, via the best LFS, (fish will never be in the LFS tanks, they recommended this - sounded good), and put them all in at one time, (after major water change).? Think this will work?
<Mmm, possibly... hopefully no, little nitrogenous, other cycling issues... You're doing this to lessen the chances of agonistic behavior? To save time, money on freight? What re quarantine procedures?>
... so ... After six weeks of water, the side of an overflow cracked from the bottom outside corner, where the tank bottom meets the side, up 10 inches at a 45 degree angle, towards the center of the tank, across the whole width of the side of the overflow. The overflow trickle leaks into the overflow only, at the crack, when empty. There is no outside leak. This means if there is a power failure, the 29 in high homemade 1 1/2 in. Durso standpipe will drain the tank down about five inches from top, (to the bottom of the inverted trap/street L), overflowing the wet dry sump by maybe 20 gals. The Glasscages recommends drain, cut out the caulking ... silicone a glass patch to the inside or outside of the cracked pane, and re-caulk.
<Yes... this is what I would do as well>
They say this normally happens because of homeowner leveling/flattening problems. Wish I could find an angle off on this stuff so I could correct it and have more confidence.?
<Mmm, floors under load are often different then when tanks are empty... a good idea to fashion something... at least a piece of plywood under all to even all out a bit... better to make a more standard support (two plus by...) and set the tank/stand on this... But, it may well be that an investment in a structural engineer is in your future here.... See your "Yellow Pages"...>
Am hopeful it was just a glitch, like a pre-existing crack/chip, or glass measurements/tolerances off, or forgot/didn't put enough silicone under that piece - oops. Is this a coin flipper, or what do you guys think?
<Glass Cages make good products in my estimation... Impossible to tell re all the work from here>
Will wait for your wisdom before I do anything ... and ... I have a fish dream.
<"Brothers and sisters">
Am starting them together as juvenile's. 5 veil angels, 8 boesemanni rainbows, 8 Congo's, 5 clown loaches, 3 Bala's(-or-3 tinfoil barbs), 1 gold Severum, 1 stripe headstander, 1 red hook silver dollar, and 3 Siamese algae eaters.? Is this a good load for my 175 net gals? How would you modify?
<Mmm... well... I'd settle on either a more calm (centering on the Angels) or brisk (Tinfoils and Red hook) mix/theme here...>
... aanndd ... Am planning a battery back-up to run an air stone. Could you recommend a comparable/ better air pump than the super Luft 38 - 22w (also, to put in the cabinet to keep the moisture down, and run a stone with a one way check valve)?
<There is no better choice IMO>
... Is there a comp/better heater than a won bro titanium pro? ... Is there a recommended battery air pump? ... Mucho Thanks for your help, Andy
<I do like this heater... Bob Fenner>

Tank Repair
Hi
I've read through your FAQ on repairs.  I just bought a second-hand 2ft*2ft*4ft tank (about 100 gallons I think - we work in litres in the UK) and managed to crack one of the end panels quite badly. The way I see it I have two options: Brace it both inside and out - which I'm pretty sure would be strong enough as the tank has built in glass corner filters and lots of bracing.  It won't look pretty but would it hold? the tank is made of 10mm glass.  So I was thinking of bracing it with 10mm on the outside ( a complete panel over the whole thing) and 8mm on the inside.
Or I can dismantle the whole thing and replace the panel and re-glue it.  I've built tanks previously - nothing quite this big but I'm pretty confident.  This would be a nightmare however because of all the bracing and built in corner filters (10mm glass no less).
Is there anything I can use to dissolve the silicone glue if I go for this option?
Please don't recommend I buy new because it's almost not an option - prices over here for tanks are not cheap.  To buy the glass and glue would be the fraction of the cost of another tank - even a second hand one.  I got an amazingly good deal when I bought this one. (the usual price for a second hand 25 gallon).
Any suggestions/recommendations would be helpful.
Thanks, Mr. Meirion Jones
<Hi Mr. Jones, I would recommend replacing the panel with an exact replica from your glass/glazing store. Probably the best tool for removing the silicone is a sharp razor knife...be careful to cut only where you intend. Make sure you cut down to clean glass and plastic or metal frame, then reseal with new silicone to adhere where needed to avoid leaks. Sorry I don't have any shortcuts. Should make a nice tank when it's repaired! Good Luck!  Craig>

Cracked tank
Hi
<Hi Meirion, PF with you here tonight>
I've read through your FAQ on repairs.  I just bought a second-hand 2ft*2ft*4ft tank (about 100 gallons I think - we work in litres in the UK <Yep, that's approximately what I get, about 430 litres>) and managed to crack one of the end panels quite badly. <Ouch>
The way I see it I have two options: Brace it both inside and out -which I'm pretty sure would be strong enough as the tank has built in glass corner filters and lots of bracing. <Don't underestimate the force generated by all that water> It won't look pretty but would it hold? <I'm not sure, my field of engineering is telecom, not materials or hydrodynamics. But, going on gut instinct, I'd have to say no> the tank is made of 10mm glass.  So I was thinking of bracing it with 10mm on the outside ( a complete panel over the whole thing) and 8mm on the inside.
Or I can dismantle the whole thing and replace the panel and re-glue it. <IMO, you should go that route. A pain I know, but better safe than sorry.> I've built tanks previously - nothing quite this big but I'm pretty confident.  This would be a nightmare however because of all the bracing and built in corner filters (10mm glass no less).
Is there anything I can use to dissolve the silicone glue if I go for this option? <I've looked on the web, but I can't find anything. It seems to me the best option would be to remove the broken pieces and remove the remaining silicon with a razor.>
Please don't recommend I buy new because it's almost not an option - prices over here for tanks are not cheap. <Ok, I'll hold my tongue> To buy the glass and glue would be the fraction of the cost of another tank - even a second hand one.  I got an amazingly good deal when I bought this one. (the usual price for a second hand 25 gallon).
Any suggestions/recommendations would be helpful.
Thanks
Mr. Meirion Jones
<Hopefully that helps. I'd recommend you check with the DIYers over on the forum: http://wetwebfotos.com/talk/ or at OZ reef's DIY page: ozreef.org/diy/ Have a good night, PF>

Crack in My 150 Gallon Tank!!
I just moved over the weekend and during the move I cracked the back glass on my 150 gallon tank!! the crack is in the shape of an "U". It is in the middle of the glass. I live in Inglewood, Ca (near Los Angeles). Where can I get the tank repaired?  LaTrice
<Bummer :( The best I could say is to contact local glass shops or fish stores to find someone to do this. Good luck, Don>

Crack in my 150 gallon tank!!
Thank you for your response. If I had a sheet of glass cut and replace with a sealant and tape. would this hold with all the pressure?
<Oh no, this would be an accident waiting to happen. Basically the tank has to be totally separated and reassembled using 100% silicon sealant that does not have any additives. This can be a daunting task on a larger tank, but if you find some help and go slow, it can be done. You can try to seal in just the replacement side, but it very likely to leak and you have to tear apart the tank and do it anyway. You can find several discussions here http://www.wetwebmedia.com/aqrepairfaqs.htm to see if you want to proceed. This site http://saltaquarium.about.com/library/weekly/aa050200.htm has a discussion and stepwise instructions for replacing a pane of glass. Unfortunately, many folks just buy a new/used tank. Hope this goes well, Don>

Fix-a-Chip?
>Hello,
>>Hello.
>I have a 45 gallon tank I bought about 6 years ago.  I moved it about a year after I bought it and found that there was a small chip in the corner on the outside of the tank.  The silicone inside was still in good condition.  I filled it, and used it as a marine home for my 2 clowns, firefish, and shrimp.  About a year and-a-half ago I moved again and bought a 46 gallon bow-front.  I put the 45 gallon out in my garage in case I wanted to use it later.  (It is currently sitting just on the garage floor)  My question is, as I live in Wisconsin and it gets very cold and because of the chip, could there be any further damage to the tank that I should no longer use it?  I have watched the chips closely in the changing temperatures and no cracks have started.
>>It is less likely that the chip itself would present a problem than it is the silicone would.  Even if there were cracks beginning, there are a couple of different ways to make repairs.  I would let it be, and do the usual routine before using it again (fill it with water in an area that WON'T be damaged should it leak - let it set for two to three days).  Marina

Fix a crack
Back again, different subject... I have a 96x30x30 glass aquarium 10mm thick glass. During a move the tank was set on a tiny stone (fish tank type tiny little stone!) and a crack about 10 inches long was the result. I have heard of repairing glass tanks with another piece of glass placed upon it and silicone to hold it together, (The tank is laminated glass, but I am still worried about refilling it!) How is the silicone placed on the break? Is it placed on the break and the glass overlaid or is it placed on the cover piece and all over? also, what size should I use to cover the crack? Thanks!
<Is the crack in the bottom pane? I would have a 3/16" or 1/4" or equivalent sheet of acrylic/Perspex cut to fit the inside bottom, as close to the edge as possible... and silicone all around the edge as well as the cracked area... AND a smaller piece of the same material cut and fit over the crack from the bottom... AND set the tank up empty, fill it with water (after the silicone cures a few days) and see if this repair is going to hold. KNOW that these sorts of breaks can be EXTREMELY dangerous... if the tank gives way it not only will cause a huge mess, it could result in very serious injury, even death to anyone near or under it at the time. Bob Fenner>

Big cracks in
Hello,
<I say a greeting>
    I found a 55g the other day, needless to say one of the short side panels has multiple cracks running the length of the pane.
I think my options on fixing it are removing and replacing the whole pane. I'm not sure that siliconing a pane on either side of the broken pane will be effective or safe. Am I correct in my thinking?
<Not worth trying... best to cut out old one, replace entirely>
    I would rather not tear the tank down, clean and rebuild it as the cost of a piece of plate glass would be close to what I can buy a used non cracked tank for.
<Bingo! If cost is the only or primary consideration, I would buy a new tank, make the old one into a non-aquarium... perhaps a terrestrial planted paludarium...>
Now that I have dragged this into the basement though, I would like to do something with it.
I am wondering if 55's are made with plate glass or tempered glass?
<Almost all with plate>
If it is plate, I think I can cut it for lids for some other tanks, use the good panes for a plywood tank, or cut the panes and put them back together as a smaller tank.
    I do have some experience cutting single and double strength glass from the hardware store. I've never done anything that big though.
Thanks for any advice.
Peace,
-Z-
<I would get some help... have a glass shop cut the glass for you if you have any concerns... or lack a cutting table big enough... Bob Fenner>

Repair plans
I have a 72 gallon bow front.  I developed a crack in the center bottom of the back panel.  I know without replacing the panel the tank is shot with regards to fish.  However I am considering partitioning off the tank so the back center of the tank would remain totally dry while the front and sides would contain water.  It would then be designed into a herp tank.  My question for you is this.  How deep can I make the water without threatening tank integrity.
<Likely enough... a few inches (3,4) >
I would like to take the water depth up to 5-6 inches to allow for a good aquatic environment.  This would put water about 5 inches above the weak point in the tanks back.  The crack would be sealed and patched and glass siliconed in to isolate about a 10 x 12 area that would hold small potted plants and substrate.  Do you think this would be to deep?
<With this repair you should be fine>
I know about old and new silicone troubles and will use acetone to prepare for the interior walls.  
Thanks, Kathy Brinson-Wagner
<I say press on with your project. Bob Fenner>

Cracked
>I was writing in regards to my cracked fish tank. I believe it is a 35 gallon fish tank and we had a crack from the bottom to half way up the side of the tank. It is an octagon fish tank and it was not cracked completely through to the inside so we decided instead of trying to take the glass out, we would just get another piece and put it on the inside of the tank and seal it back up and see how that would work. Well while checking it for leaks the glass on the outside cracked even further all the way up the tank but it was only the outside not the inside. Is there any suggestions that you would have for us other then what we've done? We plan on taking the glass we put in back out and trying to seal it better this time, because the first time we didn't spread the silicone flat we just put it in as smoothly as we could. Could that have been the problem? Thanks for your time. Tasha Duncan
>>Well, Tasha, that would depend on whether or not the crack extends to any joints. If so, then the only repair is to remove ALL the silicone (and I mean every little bit) and replace the panel. A local fish shop might be willing to do this for you. If you want to do this yourself, then search our site on "aquarium repair". I and others have outlined methods. If the crack does not extend to any joints, then if you wish to sandwich, you MUST be sure of a few things. One; that the silicone beads have NO air bubbles in them. Two; that you place the glass, press into place, and do NOT allow it to lift at all - this will create bubbles. Three; the glass being used to sandwich MUST at least be as thick as the original, and it MUST extend to all sides, corners, etc. Essentially what you're trying to do is completely seal off the crack from all water access, while creating a physically stable panel as well. Marina

Large glass tank... cracked bottom
I just purchased a 300 gallon fish tank and the bottom glass CRACKED I mean cracked during transit. I live in/around Chicago Illinois do you know anyone that safely replaces this glass?
Thanks Larry Watson
<Unless the crack is small, across a corner where it can be isolated, sealed over with a repair piece entirely (the whole bottom) I would do as you suggest and replace it. This is best done by the original manufacturer or their assigns (ask them where they will warrant the repair). Bob Fenner>

Glass sides Acrylic Bottom
Please give this your best shot,
I have a 300 gal glass tank with a broken bottom. ½” Acrylic is much cheaper than ½” glass. Any cons to replacing the glass bottom with an acrylic one? I have a steel plate stand so the weight is distributed evenly. Will the silicone adhere to the acrylic and glass properly?
Thank You.
Cavett Eaton
<This sort of repair can work... but not always. It is best that the existing bottom (though cracked) be left in place AND that a piece of plywood be cut, fit into the gap (if any) beneath it... as the acrylic will flex considerably otherwise. Silicone does "stick" to acrylic, but not nearly as well as to glass. Bob Fenner>

Glass sides Acrylic Bottom
Bob, Thank You!
I have all the original glass and can put it into place before I put the acrylic in. Maybe I can get away with a piece of 1/4 " plexi on top of the 1/2" glass after I trim the excess Silicone away, or would you suggest sticking with 1/2" plexi?
<If the pieces are large, with little or no gaps, the 1/4" should be fine... I would make a good job (continuous zig zags of bead) of Silicone between the glass and acrylic>
Should I rough up edges for better adhesion to the silicone?
<No, not necessary. Do lay in a good bead all around the bottom edge and smooth with your finger, a tongue depressor or such. Bob Fenner>
Thanks again!