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FAQs on Glass Aquarium Repair, Troubleshooting/Fixing

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Related FAQs: Glass Aquarium Repair 1, Glass Aquarium Repair 2, G lass Aquarium Repair 3, Glass Aquarium Repair 4, Glass Aquarium Repair 5,  & FAQs on Repairing Glass Tank: Scratches/Blemishes, Cross-Braces, Leaks, Chips/Cracks, Whole Panes, Tools: Cutting Glass, Silicone, Moulding/Frames; Techniques; Olde Tank (Slate Bottom, Metal Frame, Pecora...) Repairs, & Acrylic Aquarium RepairUsed Aquarium Gear

Question 1: Is it worth fixing? 2: Best method/s?

Wales glass bending. Hole and bowing concern    2/28/13
Hello from Wales.
I have a tank with the fish and the coral trees all growing together. It is a rooms divider and is 62 inches tall and ate feet (96 inches) in length with the wide being just 30 inches so I can get in and clean occasionally, (not me, the tank I mean). I also have real rocks inside the tank with bushes on too some of them....My batfish likes these.
I had this tank made with the very thick glass I think it was diamond white glass and was 10 mm thick all over. (I don't know what mm is but it looks nearly one half of an inch plus a bit).  The glass was very straight when the men input the tank and was very straight all along the front and back. 
Now I have the tank going for 8 months (I have a dump below the tank in my seller <cellar> with extra sea water) which feeds the water up and down. 
As I was saying the glass was very even along the front and the back but now it seems like it is a bow front tank, is this normal?
<Mmm; well, glass/es are super-cooled liquids, not really solids... and do "flow" with time; but not this short a period... likely was bowing all along once filled>
 Also there is a very tiny hole right at the bottom,
 not at the front but at the back!  I attack <attached> a picture with this mail ok?
<Yes, I see it... a puncture-caused piece is missing>
  It is a funny hole because you can actually/seriously pass a thin wire/needle right threw it and it has big round circle round this point.
<Like a bee bee or small caliber shot...>
 After much pushing and some blood getting the rubber in the hole
<Silastic I take it>
 with glue as well the piss/leak seems to stopped.
<How far below water level is this hole?>
 I did have to drain out the tank which the fishes didn't like one little bit, flapping and jumping all over the place they were!!  But now is ok, they have water back.
My house is in the sea (well not in it as such but very close) so I don't have big bills with the salt/powder to buy. I have a titchy/tiny bat fish but he is now like 2 feet tall and he eats lots of coral trees and bushes. 
(Hehe one day my porcupine shark will eat him no?).
<Not likely; Platacids are smart, and faster>
 So my friend Bob and sparky or was it scottie I used to speaks to many years ago? How can I make the front of the tank flat again please?.
<Can't be done>
I think I needs help yes? 
Many many thanks,
<As many welcomes. Bob Fenner>

Tank Panel Deflection 2/17/09 Scott, I just got a 75 gallon tank made. Its up and running. I noticed a slight bowing in the front viewing panel of the tank ~1/8" out at this point. Tank front is 3/8" should have opted for the 1/2" thickness. <3/8" is standard for this size tank, no worries.> The manufacturer claims it will hold in the long run. I was just wondering, as i start to fill the tank with live rock and displace about 30 gallons of water... will that relieve some amount of water pressure forced upon the tank panels... its a physics question. Less water=less bowing? <Nope, not at all, the pressure will be the same.> Because the rock will be weighing down on the stand and not adding pressure to the viewing panel? There would be ~240 less pounds of water pressure. Will this bowing overtime become greater and more visible than 1/8"? or reduce greatly once the rock is added...? <The bowing will be the same regardless of rock....1/8" is not bad, every tank on the planet has some deflection. Don't let this worry you, the manufacturer is correct.> -Matthew <Scott V.>

Misaligned seams - 02/08/09 Good evening, <Luke> I really enjoyed reading your sight <Site, homonym> and attempted to find the answer to my question within it, but was unable to do so. I have a 45 gallon glass freshwater tank (36" long X 24" tall) that has been running fine for over a year now. However I recently noticed that a vertical seam was misaligned on one bottom corner. The glass is approximately 7-8mm thick and the front pane is shifted over and exposing about 2 mm of the side panel. I am not sure if I bought it this way or it has been developing gradually. <Mmm, no. Was (mis) built this way> The seam appears fine otherwise with no bubbles. The tank is not leaking now, but I am concerned about the integrity of this seam since the contact area between the two panes is decreased. I am moving soon and I am debating about whether or not to replace the tank or consider it safe for future use. Thank you so much in advance for your help. Luke <Please send along a well-resolved image of sufficient size re... You are likely fine here. Bob Fenner>

Bamboo tank leaking, Repairing An Old Collectable Tank - 06/27/07 I purchased an old 35 gallon tank that has a bamboo over mahogany base, tank and cover. I tested it for leakage and set it up about 2 weeks ago. It started leaking yesterday - I'm thinking somewhere near the bottom as it kept leaking until it was totally drained. After calling around, most people tell me it isn't worth the cost of fixing and to just replace the tank. But it really is cool looking with the bamboo trim around it. do you think it's worth a try? Should I try to fix it myself? What would be a reasonable price range to get someone to fix it? Thanks for any help. Tina <These old tanks were made in the 1960's and are very collectable. Take a single edged razor blade and trim off all th old silicon on the inside of the tank. Shave the corners to get as much of the old silicon out as you can. Wipe down the corners with glas cleaner to remove any dirt or dust. Use a tube of silicon that is made for aquariums and reseal the inside. Thy make special tools for smoothing out the silicon, I just use the back of a plastic spoon. You don't want any air pockets in the silicon. Test the tank in a couple of days. Hopefully the leaks have not damaged the wood.-Chuck>

Oceanic Tank Problem?  4/16/07 Hello, <Hi Matt> I have just taken delivery of a new Oceanic Tech series 45 gallon reef ready aquarium.  It has a small imperfection in it's construction, and I'm hoping you can tell if it's a problem I should worry about or not. The side panels are siliconed in between the front and back panel.  The imperfection is that the right side panel is not installed perfectly square.  At the joint with the front glass the side panel is depressed by about 1mm.  The joint between the right side and the back panel is flush at the top, but the side panel protrudes slightly from back panel at the bottom of the joint.  The tank seems generally overbuilt, if I'm measuring correctly the Starphire glass is 12mm thick. Should I worry about this? <No, but I would make the quality control issue known to Oceanic.> Thanks in advance. <You're welcome.  James (Salty Dog)> Matt Harrop

Please Help with Tank seals!!!  -- 4/9/07 To Robert, I am not a manufacturer of tanks so some of the finer points elude me I hope you can assist me. I was wondering if you could inform me as to the common or uncommonness of air bubbles stuck inside the silicone seals of a tank with large seals the tank is 96x45x24. <Not uncommon...> I have a few bubbles in the seal, mostly on the bottom some more than 1/4 of an inch, <... I don't like them this large...> when I attempted to fill the tank the bubbles stretched on the outside panel <!> in the seal almost coming up to the gravel at the bottom of the tank I had it 3/4 of the way full the bubble was almost 3 in long (the seals are almost 4 in long and triple paned at the edges for seal), <?...> I had emptied it rapidly and the bubbles shrank back to mostly normal I believe the bubbles are now more apparent and possibly even a few more than to begin with. Any Ideas? <From the dimensions, I take it this is a custom job... by a large manufacturer? Triple paned?> Does this make it unstable? <Mmm, unable to say... wish I was sure that whoever made this tank had seen, has seen this/these defect/s...> I just want a few outside professional opinions as to this situation/condition. I am talking to the manufacturer as well, <Ah, good> as a side note this is the second tank, the first one we got had faulty seals to the point it exploded in the office. <Yeeikes!!!> All the info I have about the manufactures is good stuff great looking tanks and from speaking with them very knowledgeable, the owner has been making tanks 18 yrs. They are investigating the problem and likely to recommend the re-fill of the tank, I cannot have another tragedy happen as it would likely ruin me/ destroy my confidence in glass tank manufacturers all together. <Mmm... would you please send some images of these air gaps... with the tank empty, filled... not changing the settings of the camera, or its distance from the work?> P.S. I love your book read it years ago, recommended it to hundreds of people as a great no-nonsense read. Thank you for your time,
<Welcome. Bob Fenner>
Re: Please Help with Tank seals!!!  -- 4/9/07 here are some of the pics of the seals.  there is a shadow above some of the bubbles in the pics, the shadow is the growth from filling. thanks, Dan <Good pix... from what I see these bubbles shouldn't be a problem going forward here... May seem not to matter, but I would place some sort of visual barrier (even just stout tape) around the base here... to "take your mind off" these defects... But there seems to be sufficient seal area for this depth/configuration of system. Bob Fenner>
Re: Please Help with Tank seals!!!  -- 4/9/07 hi Robert, thank you for your quick response. it is very reassuring. I've just heard back from the manufacturer, and from the photos they feel that a section of the seal is wet. and want me to remove all the gravel and decor, to allow it to dry for one week. do you feel removal of the gravel/ decor will make a difference? <Yes... if this "wetness" is/was the matter> as a side note, the manufacturer took three months to replace/ send the tank and one week for shipping. your thoughts would be greatly appreciated. <... So... when in this time frame was this tank/glass assembled? If more than a week or so... the Silastic/Silicone should not be "wet"... Am dubious. BobF> Thanks a Million,
The Aquatic Doctor
tank seals????  -- 4/9/07 hi Robert, <Doc> so I gave copies of the emails, regarding the seals, to my clients and they would like a "tank expert" to come out and look at it. after I had explained who you were and why I was trusting your opinion, they told me they wanted me to get YOU out here to look at it and that they are more than willing to pay you. so they wanted me to ask you to come out and take a look. I'm asking, would you be willing to come out and take a look? <Heeeee! I do work in the trade/interest as a consultant... but am out in HI, and my time is pretty much committed in to 08...> if not I understand. and I have been instructed by my clients, to fill the tank tonight, because they believe if it does go wrong it is just shoddy craftsmanship. thank you so much for all of your help, daN <I do agree with the gist of your customers sentiment... I do understand the rationale behind some fabricators building multiple glass panel bottoms, not joining the sides, front and back directly (down) onto the bottom... but don't agree with this methodology... for obvious reasons... a small strip (a couple of inches) can be fashioned, adhered into the joints with silastic... with as much added strength as the current design... w/o all the weight added, or concerns with Silastic curing. BobF> Thank you your Business is Appreciated! Daniel
Re: tank seals????, consultancy  -- 4/9/07 Hello Robert, I am sorry about the spelling, its been a long day. I assumed you were busy, do you happen to be able to recommend someone around or near Pasadena C.A. that has extensive knowledge of tank construction and curing. I tried pushing on the pane of glass something about the bubble in the middle of the front seal seemed wrong, and sure enough I was able to 'float' the bubble between two and a half panels of glass. <Mmm, yes... first try, a friend in the trade, Jim Stime... am Bcc'g him here> The seal is definitely still wet deep inside near the bottom, I think the top pane closest to the gravel is cured as the seal is a different color than the bottom seal. <Mmm, well, the closer the Silastic is to an edge... where it will, would come in contact with air...> My clients are mad and of course blame me for recommending the manufacturer. I am trying to resolve this as soon as possible I am trying to find out what kind of silicone mix they used in construction. <... an interesting comment... Should NOT be a mix...> Any help you can give would be greatly appreciated. It is an honor to talk to you. <There is much to state, speculate... too much for this mechanism of writing back/forth in the short term> P.S. Thank you again for your quick responses, I know its getting late must be a great view from HI <Ah, yes... Jim? You can see the pix et al. Daniel has sent along on WWM's Dailies today. Bob Fenner> Daniel The Aquatic Doctor

Foggy Glass - 04/02/2007 Hi Guys! <Hello, Bob!> When my tank is empty, I notice the glass is very "foggy" when dry. It's not "clear" but rather opaque, discolored.   <This is "normal", so to speak.  Mineral deposits from the water cause this, and it's really not harmful at all.  If you intend to fill it again, you can ignore this fog.  It will "disappear" when the tank is filled again, unless the buildup is quite extreme.> Is there some way that I can restore the glass to its original clarity and luster without harming the inhabitants (when they are returned to the tank)? Anything you can recommend? <Vinegar may be quite helpful, here.  It is a mild acid and can be rinsed cleanly away.  If you require something stronger, Muriatic acid (used in swimming pools) can be used, but requires a lot more caution than vinegar.> Thank you,  (again!)  -Bob <All the best to you,  -Sabrina>  

Air bubbles in 200 gal. Glass Aquarium Seams   3/26/07 Hello to Wet Web Media's Crew Members, <Thanh> I recently bought a brand new 200 gal Visio glass tank to set it up as saltwater.  The stand is a DIY stand, all 4 corners are level, however the middle/back/sides are a little low. <Mmm... as in light showing under? Not good...> The glass tank is resting on a 3/4" plywood. <Oh! And this has provided a continuous support along the entire edge I take it. Sometimes screwing such a piece of wood into the stand below will provide such a continuous support (needed)> After 2 weeks, I noticed there are some air bubbles inside the 2 back corners of the tank, there are also air bubbles inside the 2 corners of the front seams, however not as much as the back seams. I don't remember seeing the air bubbles inside the seams. I was probably too busy setting up the live rocks and stuff and fail to check the seams at first.  The plastic molding/bracing along the top/bottom are still intact and in good condition. <Good> I went back to the store and look at other tanks and noticed that there are air bubbles inside the seams too, but not as much as mine. <Does happen...> Please look at the attached pictures and let me know if there are a chance the seams would leak on me. The bubbles are in group and on the bottom corner only. I was thinking of buying a 2" wide and 10" long piece of glass and seal/bracing it from the outside covering the join area of the seam/glass. Would this help prevent the air bubbles from expanding? Thank you for your help. Thanh H. Tran <I am concerned re this situation... the air/bubble gap you show is dangerously large and placed... Is this gap in the actual joint, between the panels of glass here? Not (just) in the corner bead, that is inside the Silastic in the tank nestled in the joint? If it is between the actual glass panels, I myself would have the seller/store come by, take a look, and VERY likely take this tank down... have them replace it with one that does not have this manufacturer defect. There is a possibility that the seam may fail... Particularly from ground movement... I see from below that you too live in S. California... Do have the LFS mgmt. come by and have a look-see. Bob Fenner>

Re: Air bubbles in 200 gal. Glass Aquarium Seams   3/26/07 Wow, Thank you Mr. Fenner for your fast replied I am greatly appreciated. <Welcome Thanh, Tom> Yes the tank bottom is resting on a large solid 3/4" plywood.  All 4 corners are level, however the middle of the tank, back, and sides are a little low. The tank molding is sitting on the plywood solid, there are no gap at all. <Mmm... do consider the previous suggestion... when you switch these tanks out... to use some non-ferrous screws of size (Brass maybe)... or bolts, washers... counter-sinking the heads... to "bring up" the plywood support and stand edges together> The air bubbles are inside the silicone, between the join of two pieces of corner glass. Not outside. <Trouble...> This tank is a 200 gal (84.5"by24.5"by25.5"tall) and there are two large pieces of glass on the top bracing both sides of the tank.  I am surprised that there are no silicone outside the joins. <Mmm, not really functional... in terms of making the tank water-proof... but of use in preventing tools jabbing inside the actual joint...> If I run my finger outside the joins/corners of tank ( inside or outside of the tank ), I can't feel the silicone.  The silicone is actually inside the join only. <Yes, this is fine> Again thank for your help, I will contact my LFS.  But if they turn me down by saying it's okay, would you recommend placing a 3" wide by 24" tall pieces of glass outside of the tank, silicone it against the joins on both sides ( the back ).  This is like bracing the corner so it prevent it from bowing/opening/leak in the future. <No. I would NOT do this... for a few reasons... for one, I doubt it will "work"... and secondly, it may well void any stated or implied warranty. IF your LFS won't replace this tank, DO contact the distributor, manufacturer... and if necessary, the State Attorney General's office. Do feel free to show all this email> I will have wave box and 4 x 6100 Tunze install in this tank, so I don't know if the seams would hold the high flow and the power of the wave of the wave box. <This is actually a very minor source of sheer and/or lateral force... compared with the weight of water, possible torsion from the stand, the impact of a sudden movement (like from an earthquake)... Not to needlessly worry you... and there is nothing like actually seeing this set-up in person... But I would have the store come by... BobF> Tom

Glass aquarium repair  4/28/06 Hey guys,    <And some of the tender gender>   I have looked on several sites but have not found anyone else with my problem.  Currently own several tanks including a bowfront 46G and a generic 55g. <Not a problem> Over the past 5 months, both of these tanks have been sitting outside in hot/humid Florida with no water inside.  After bringing them inside and washing them in order to reset up, I noticed air bubbles along the seal of the 55 (actually on the inside of the seal not in contact with the air) and on the 46 bowfront the glue is slightly separating from the glass (not enough to leak but its there.  The tanks don't leak (at least not enough to be noticed) but I want to avoid the coming BOOM and soaked carpet.  I am thinking of resealing both tanks to prevent the waterfall.  If they aren't leaking, should I bother with the reseal? <Mmm, I would not... if these were commercially made, there is more of a chance of trouble with cutting out, replacing the Silastic than not. I would test fill these tanks in a safe place... on stands... and see if they leak.> If/when I release, do I need to be using clamps or how should I keep the glass steady and square?      Thank you      Your avid fan,      DK <Can be clamped, even just sturdy-taped if the panels are set on a level, planar surface during construction, particularly if the bottom is not "floated" (i.e. the sides, front/back viewing panels are set on it. Bob Fenner>

New Aquarium Seam Question (Pic inc.)    2/12/07 Hi, <Hello there> I love your forum and you have answered many questions I have had.  I currently am running a 75-gallon freshwater community aquarium which I have had up for about 4 years.  Now, I'm wanting to take the plunge into saltwater. <Ze plongee!> I recently bought a new Perfecto 120-gallon aquarium.  Upon getting it home and filling with water for a leak test I noticed one of the seams looked a little funny. <I see this> The included picture shows the seam in question.  It is the upper two-thirds of the seam.  The lower third of the seam is clear. <The better area for this> I researched seams in your FAQ's and found that some bubbles are normal but I'm not sure if these are too much or not. <Mmm... this one is likely fine... and it seems you have a pretty good idea of how this happens... just not a "great" job of putting this tank (seam) together>   The aquarium was full of water for about 3 days with no leaks.  Could these bubbles be problems down the road? <Mmm, not likely> Seeing as the aquarium is new, should I just return it or should I keep it and not worry because the seam will be O.K? <I would keep it... the possibility of a problem is low... and am admittedly too lazy to take all out... move this one for no "good" reason>   I'm not trying to be too picky, but the prospect of 120-gallons of saltwater in my floor kind of makes me uneasy.  Thanks in advance for your help! Paul H. <I understand, and agree! Bob Fenner> Re: New Aquarium Seam Question (Pic inc.) Wow!! Thank you so much for the quick response and detailed answer.  Personal answers in a day!  You guys are fabulous!  Apparently, you are genuinely interested in furthering this hobby. I'm going to keep the aquarium and press on.  Thank you again! Paul
<Welcome my friend. BobF>

Cracked bottom, scratched second-hand glass tank repair  2/28/07 Hiya...I have a few Questions about a second hand tank i have bought. I have read through many of your articles but don't see any about cracks on the bottom. only sides. <Mmm... bottoms can be tricky... as most all tanks are "made" on their bottoms... the sides, front, back Siliconed down onto them...> The glass is 10mm thick and on the bottom there is a scratch/crack about 1 foot long. I can only feel it on the underside of the tank and not when i put my  hand inside the tank.. (The tank is still empty).  I was wondering what the best option for this would be. Would this make the tank weak? <Mmm... yes... It may be possible/practical to effect a repair by cutting out the entire seam inside the tank (including the sides, yes)... and fitting a new piece of glass inside, over the existing cracked bottom... Siliconing over the crack, and all the old/new corners... if the bottom is "very badly cracked", as in pieces missing, another piece of glass should be fitted, Siliconed in over the bottom as well...> I  thought about siliconing another smaller piece of glass onto it. <Mmm, not small... Really needs to fit "corner to corner"... though not tightly> I don't really  care if it is not leaking just peace of mind wants me to do this, so i have not  even tested for a leak yet. <I would not test it for such... it will leak, assuredly... and a simpler repair I would not trust> There are also 2 chips 1 at either end of the tank ..in the middle at the bottom, where the side meets the bottom. These are also not right through, but would this be a weak point? <Yes...> I hope you are able to make a little sense from that lol Thanks ...Jade. <Yes... Reciprocally, do my comments make sense to you here? The rationale for cutting out, replacing the existing Silastic is that way-too often there are leaks that originate "somewhere" when all the inside beads aren't of the same age/continuous... See the Yellow Pages, folks at a glass shop... 100% Silicone (no mildewcides...). Bob Fenner> Old Aquarium, sell... or repair?   2/22/07 I visited a local pet store and inquired about repairing a 55 gallon aquarium that has been sitting in my mother's garage for 20 years.  I am 63 years old and I remember my father having fish in that tank when I was a child. Obviously, it is close to 70 years old; it is on a metal stand with wheels. <Neat!>   The aquarium has a slate bottom with drain hole that appears to be in good shape.  The problem is that one of the larger glass sides was broken and needs to be replaced.  I have considered selling it in a garage sale or just giving it away, but the pet shop owner indicated that it might be of some value. <Yes; might be> He said that he doubts that a replacement glass would be advisable thinking it would probably leak and thought it might be better to use it as a terrarium.  It occurs to me that if I installed glass of appropriate thickness and was successful with sealant application, the aquarium should be adequate to maintain fish.  What would you advise. <Mmm, well, unless you're in a big hurry, I'd "shop" it around... see what it might sell for... And if all you're interested in is having a useful system... I'd trade it in for the money and buy a brand new outfit. OTOH, I do like antiques in the field... so, repairing it might be the way to go... with "matching" technology (likely Pecora sealant...)>   If I were to install a new glass, could I purchase the glass from a local retail glass dealer? <Mmm, yes... if this were the route you settled on> What thickness would you recommend. <Likely 3/8 or 1/4" plate... The latter likely being what it is otherwise made of> Also, is it your opinion that the aquarium I have described would be of value as an antique?   <Yes... And I do encourage you to contact an old (okay, middle-aged...) friend, Gary Bagnall... of ZooMed... who is about the most "in to" person of such gear that I know... Have cc'ed him and another hobbyist/collector friend, Chuck Rambo here... And maybe try a pic or two... on eBay...> Thank you for your assistance, Charlie Marsh Jacksonville, Arkansas <Welcome, Bob Fenner>

Aquarists worst nightmare... So I woke up at 2:30 am last night to every aquarists worst nightmare.. the sound of gushing water.... The front pane of my 40 gal. reef  split from top right side all the way down to the bottom. Grabbing all the Rubbermaid containers, and buckets I could I ran out there and tried to catch as much as possible.. I think I saved about 15 gallons, while the remaining 15 or so marinated the wood floor. Some good news though. Ran out to the store first thing this morning got a new 30 gal tank, I think all corals, fish, crabs, and snails survived, and are now living happily in a (slightly cloudy) but new tank with a brand new 6 inch sand bed. (I was lucky enough to have 90 lbs of  aragonite still out in the garage..) I tried to save as many sandbed clams as I could from the old tank, but only found about a dozen.. ( I couldn't find about 6) not to mention all other life such as worms, copepods, and other misc. bugs that were flourishing in the old sand.. (I couldn't put the sand it in the new tank, b/c of the toxic sulfur dioxide that I could smell after stirring it up looking for my clams.) lessons learned: * Can never have enough buckets, and towels around in this hobby.... * Always have spare heaters and powerheads... * Lastly, (and by far the coolest) Cerith snails are the hardiest things on the face of the earth... I took the tank outside last night after draining it, so it wouldn't spill any more muddy muck all over my floor.. I went out this morning, ands on top of the sand were 5 dried up Cerith snails that had been outside, out of water, in 38 degree temps for 8 hours. I thought what the heck and threw them in the refugium, and within 5 minutes they crawled up on the glass. Who'd a thunk? Any who, my zoanthid fragging will be somewhat delayed due to these unforeseen circumstances. Just wanted to share my story with my fellow reefers. Ciao. J. Blair Miller <Thank you much for sharing... What an ordeal! Glad to see your intelligence, balance has survived along with most of your livestock. Any idea what caused the tank to split? Bob Fenner>  

60 Hex Sealant Lifting I didn't want to post a public chat because the person that I purchased this tank from and the LFS that assured me it was ok use your site. <Okay> The problem is this: I purchased (for my employer) a used 60 gallon hex, cleaned it up, and immediately filled it up and had it running with a power pump in the basement for about 6 weeks while waiting for our new office to be ready. <Good idea> I then emptied it and brought it to work to set it up. A fellow aquarist pointed out that the seals were yellow and lifting. <Lifting!?> We even found a pinhole sized hole on one seam halfway down one inside seam. (Coincidentally I came across someone in one of your articles that had a pinhole sized leak halfway down with a 60 hex). <Yikes> It seems that I should head off any future problems by cutting off the rough edging and resealing it with aquarium sealant. Needless to say a leak at work would be disastrous. I am, of course, upset that I was sold an aquarium with this potential problem as I was assured by the seller and the LFS that the seals were fine. Is this a real, potential disaster or am I being overly cautious? <Hard to say w/o first-hand observation. Was this tank resealed? Or is this the original?> Is it fixable or should I just try to get my employer's money back? (I am having problems with the canister filter that came with it too.) It was only $150 so I might be better off just giving back my employer the $150 and chalking it up to experience. It is sort of a no win situation...please let me know your thoughts. <I share your concern re the seal... it should NOT show signs of disengaging from the wall... Now, know that the actual silicone in the glass joints is largely non-functional, in that it does not do much to hold the tank together... It's more for protecting the actual between-glass silicone from damage, like from a cleaning (razor) tool... And know that a sixty hex is much better than a 75 or 90... that have the same base dimensions, but are much taller... a sixty is 24 inches in height if memory serves... So... w/o seeing it I am not so/very concerned... and you did test it for six weeks... I would at least have another old-timey aquarist come to the sight and check out what you have... and if you can make them, send along pix of what concerns you. Bob Fenner>
Re: 60 Hex Sealant Lifting Wow.  Did not expect to hear from you personally.  I love your book by the way... Will get pictures to you sometime tomorrow.   <Ahh, look forward to seeing this/these> Thank you so much for your time, Elaine <Welcome. Bob Fenner> Re: 60 Hex Sealant Lifting Attached are some pictures of the inside sealing. Two are of the pin-size hole that I found that does go quite a way in (to the outside sealing).   <I see what you mean... looks like the folks doing this job (and it does look original), were using some old Silicone, and/or doing this work quick on a hot, sticky day... None the less, from what I see I would not be concerned> The outside sealing is clear and looks real good. <Yes> Thank you again for taking the time to help! Elaine
<A pleasure. Bob Fenner>

New aquarium repair I just received a 96x30x30 Starphire aquarium from Inter American. The front and side panels are 1/2 inch Starphire the bottom is 3/4 and the back and Euro- bracing is 5/8 regular glass. The problem is that there are hundreds of bubbles in every seam of the aquarium. The bubbles are large some around an inch long. Inter American said that it was normal to have this many bubbles because the glass is tempered <?> and they will not give me a refund. When I fill the tank about halfway the left front seal turns chalk white. <Not good> It first turns chalk white only at the bubbles but then I can see the white areas spreading the longer it sits. They told me to let it sit empty for a few weeks to let the silicone harden more and that everything would be fine. <Umm, the Silicone "hardens"... little... it cures in a day...> I'm guessing they are just lying to me and this problem will not fix itself. The only seam I have seen turn chalk white is the front left but every seam has hundreds of bubbles even the seams of the Euro- bracing. Can I fix this? I do not have any experience with building or fixing aquariums. Thanks <Fixing is difficult... requires cutting out the seals... including between the glass (the only functional seal)... I would be talking with your/their States General Attorneys re the legality of this sale, lack of exchange. Bob Fenner>

Eclipse leaking Dear Crew, <Phil here!> I have an Eclipse 3 system on a 37 gallon tank.<I had an Eclipse 12 system for a while>  I have a continuing problem with what appears to be condensation collecting inside the hood, then dripping down the back of the tank on the outside.<I had the same problem> My only solution so far has been to put plumber's putty along to back of the tank (on the outside), sealing the gap between the hood and the top of the tank. Surely there must be a better way? <Well Eric I wish I could say there was!  I have yet to find a "good" long term fix for this problem.  I have tried putting small amounts of paper towel in-between the hood and the top of the tank.  I've saved your e-mail and am going to try and contact Marineland and ask about this problem, in the meantime try the paper towel!!>       Eric <Good luck...be in touch! Phil>

Tank leaking? 3/25/03 Sorry to bother you again but this time it is rather serious.... <no worries my friend> Yesterday I realized that there was some water coming out of the top of the furniture where my tank is placed. At first I thought that it could be due to high evaporation and I opened the cover of my tank. The water still came in slow rates out of the same place: below the tank and between the tank bottom and the furniture, dropping on the floor... What a mess!!! Then I started inspecting the tank all over, trying to locate some drops on the side glasses of the tank....nothing. <hmmm... do put a "spirit level" on the tank to see if by chance the wet spot is the lowest point on the tank (assuming the tank is slightly off balance). You may not have a leak... the water could be from "capillary action" which occurs like a siphon from equipment (like a hang-on filter or skimmer) clipped over the top of the tank. the plastic acts like a wick and water in a full tank can be slowly migrated up over the edge of the tank. Check under/near those filter with a dry paper towel to see as well> Today the drops are still coming out of the tank from the same point, and I think I know why: 2 weeks ago I ordered a Remora skimmer and I connected it with an EHEIM pump 1250 lit/hour. The pump is very heavy, so I decided to put it on the bare bottom of my tank and on the glass. I suspect that it cause some crack to the bottom glass because of the vibrations. Could it be possible? <not likely at all... if there is a crack or leak, it is more likely form an uneven stand or tank (off level)> Now I have placed a bucket below the place that the drops are coming out of the tank and tomorrow I intend to catch all my fishes and give them back to my LFS , then empty the tank and try to locate the exact point of leakage, <hmmm... perhaps not necessary yet. Do check those hang-on filters> After I locate it I do not know if it is possible to fix it by placing silicone on the point of the crack. <if there is a crack, I would not repair or use the tank... it will be unreliable in the future. If it is only a leak, it may be repaired. If the tank is new... it may not have a problem at all> Will it be fixable at all or should I buy a new tank? <the latter is better if need be> Thanks, Thanassis <best of luck my friend. Anthony>

Busted Tank went onto your site, looking for some kind of quick, emergency (Mcguyver) type repair- I was in another room, heard a strange 'snap' sound went to check it out and found H2O gushing out of our 55g. while the 2 huge Oscars inside seemed to be enjoying the whole situation.  I thought quick to stop the leak; put some newspaper along the inside of the crack, from almost center of tank to corner; while being attacked by the monsters inside, was no fun ! Mean to the fullest of their names worth.  The leak subsided, I siphoned 50% of the water out,  the leak slowed. I really needed some technical advice at this point; so I went to your site, but no help as to any type of quick 911 repair. Maybe the newspaper, was it.   <Ok, take 3 pieces of bologna, a match stick, and an eraser... But seriously, I am sorry that you could not find a quick fix on our site and commend you for the quick thinking and the newspaper trick, a great idea.  A towel might work in the same fashion.  Although I have never had an emergency such as this I have had to move fish quickly and have had my share of floods, the most recent was involved the overflow of a 40gal garbage can while I consoled my girlfriend who had accidentally pinched off the tip of my lizards tail while cleaning its tank, ugh what a day.  I have a few tanks, Rubbermaid tubs, and buckets laying around for such emergencies and try to borrow my Mothers wet/dry vac as often as possible.  Although it is a bad situation, this may be a great excuse to buy those Oscars a larger tank as two large Oscars in a 50gal must have been getting a little cramped.  You might also want to look into why the tank cracked in the first place, the first thing that comes to mind is the stand not being level.  This email will be posted in our archives, and will hopefully help the next person who finds themselves in a similar situation.  Best Regards, Gage>

Trade-ins on aquariums Desperate and tired.  Have a 120gal tank that has ruptured in the seams twice in thirty days.  On the  first attempt at repair I stripped all the old silicone and cleaned the surfaces, I resealed all the seams, all the way around, allowed to dry about three days, now another seam has come loose, ready to give up on this tank, are there any businesses in the southeastern Michigan area that offer trade-ins on tanks?  I have been pricing tanks and want to save if possible                            thank you,  ellimae <Yikes... dangerous when tanks give way... and messy! Not likely that anyone will give you much of a trade-in on this tank at this point... You might be able to repair and sell it for a "herptile" use (like a snake, lizard container). A couple notes re these sorts of repairs: One, it's really important to remove all the existing silicone from the old joint... requires the use of a solvent (toluene e.g.) and clean toweling, "elbow-grease"... and secondly, critical that the tank be set on a level, planar stand of some sort... and this in turn on a floor of the same characteristics (and strong!). Elsewise, seams can/do split from uneven force. Bob Fenner>

Glass Tanks cracking Hi bob, <Hello Clive> Clive from India here. I've finally opened my aquarium store. We're having a peculiar problem - the tanks we are making ( glass sealed with silicon sealant) are mysteriously cracking on one side from one end. <Yikes!> We are taking extreme care so it cannot be because of some accident etc. Any idea why this can happen??? <Either the tanks are poorly built, highly unlikely if they're commercially made... or they are being placed on uneven/non-level or non-planar stands. Are these tanks just "hobbyist-grade"? Many manufacturers make thicker-glass "commercial" tanks that I recommend in a store setting. If you didn't make them yourself, call their manufacturer re. Bob Fenner> Thx, Clive

Tanks, But No Tanks - Glass Tanks cracking II < Either the tanks are poorly built> Hi Bob, Can you please specify poorly built - are there any guidelines or do's and don't for tank building? We are making the tanks ourselves using 5" float glass for tanks 2 feet by 1 feet. Thx, Clive <Five millimeter? Should be okay... are the tanks set on a piece of foam, some other "giving" material... i.e. not directly on the board of the supports? I would use such cushioning barrier. 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>

Removing Black Tarry Sealant (Chuck's go) I was given a 45 gal aquarium which has a chromed metal frame. The aquarium leaks around the bottom in several places and I was considering removing the bottom and using silicon to reseal. The glass and slate like bottom are all sealed with a black tarry type of sealant. The sealant has dried and hardened. How does one go about softening the sealant and removing it? < I collect antique aquariums and have a few suggestions for you. Many of these tanks actually leaked when new. They recommended that you fill them with hot water and let them sit for a few days. The putty softens up and the weight of the water reseals the tank. Try this first before you tear the tank down. Once the tank is full of water they stay water tight for years. Try and find the hood that goes with them. When they are all together they look unique by today's standards and are still quite functional. If you decide to tear it down you will need an additional piece of glass for the bottom. Sometimes the silicon does not stick to the slate so you have to cut an additional piece of glass for the bottom and them reseal the tank with silicon. Make sure that you use the silicon that is made for aquariums. The silicon you buy in the hardware store has fungicides in it that are harmful to fish.-Chuck> Denny Earle

Removing Black Tarry Sealant (Bob's go) I was given a 45 gal aquarium which has a chromed metal frame. The aquarium leaks around the bottom in several places and I was considering removing the bottom and using silicon to reseal. The glass and slate like bottom are all sealed with a black tarry type of sealant. The sealant has dried and hardened. How does one go about softening the sealant and removing it? <Good questions. First, an important note re this tank and the prospective project of removing, re-doing the sealant: Do strongly consider NOT doing this and INSTEAD saving or selling the tank as is... it's a collector's item that has more value as is than as a re-done fish tank. Now, if you want to "fix it", there is a possibility that gingerly heating the old sealant (with a gas/propane torch... careful) and cutting with hand tools (putty knives, tile knife, single edge razor blades with a holder...) might do the job, along with cleaning up the residue with an organic solvent (e.g. toluene, xylene)... OR you might have enough seal to just glom on over the existing tar material with the silicone, encasing it if you will... do all the joints, not just the bottom here. But my choice is really to save or sell this "relic" as an antique. Really. Bob Fenner> Denny Earle Glass tank repair I have a 55 gal glass tank that was built in 1991 and I need to find a replacement part.  The top of the tank has a divider bar in the center that holds the glass tops.  There are 2 pieces of glass.  This part is plastic and is connected to a plastic rim that goes all around the top of the tank.  The tank is a standard 55gal long.  We have tried to repair it but the repairs don't hold.  The tank is currently torn down and not being used.  I have someone that would like to have it but I need to get this problem fixed first.  Is there someplace that I can order this plastic rim and replace it? I would appreciate any help you can give. Carol Dunham <Mmm, there are a few very different designs used by various glass aquarium manufacturers... and the tank you have may well have been made by one that is out of business... Have no fear however, as it is not too difficult to effect a permanent repair that will add more than top support... in the way of a siliconed glass piece installed at level with the inset of the current plastic rim (to accommodate the tops, support them in the middle)... If you have never used Silicone sealant, ask about at your local fish stores for help from someone who has. The piece of glass should be at least 3/8 inch thickness (half would be better), and cut just to fit (it can be supported by books, or even tape if the tank is laid on its side. Does this make sense to you? Bob Fenner> Re: 55 gal tank top repair Thank you for your response.  My husband is a hard surface fabricator and installer.  This should be easy for him.  He works with Corian all the time and uses that type of sealant. <Ahh, good> I will let him see your email and it will all make sense to him. Thanks for all your website offers for us and we really appreciate your input and help! <Glad to share. Bob Fenner>

A leaky tank I am writing you in reference to a 60 gal hex tank that sprung a pin hole size leak about half way down on one of the seals. I have had the tank approx ten years and when I drained it, it appeared the edge of the seals on the inside of the tank had slowly deteriorated towards the center of the seal. <Rare, but this does happen in hex tanks at times> what I did was remove all of the loose silicone from the seals and resealed it with 100% silicone inside and out of all the seals. after letting it cure for two days I refilled the tank to check for any leaks. Before I did that I marked were the leak was with a grease pencil so that I could concentrate on that specific area. Once I refilled it there were no leaks but it appeared as if there was a small amount of water inside the seal. <... unusual> I then drained it and added more silicone to that particular seal and then refilled and checked to find out the water was still inside of the seal. I am unsure if the water is from the original leak or if it is from the first time that I checked for leaks. Now I have had the tank empty for four days to see if the water inside the seal would dry up and at this time it still hasn't.  my question is do you think the tank is alright to use or should I try something else. <I would set the tank up with just water in it... in the garage or some other area where it won't be disturbed, and won't cause too much damage if it leaks or worse... and leave it as such for a week>   My main concern is since I have the tank tore down I was going to try salt water but I'm worried it leaking again and getting salt water on my new carpet. Any advice on this would be very appreciated. Thank you <Bob Fenner> Rebuilding old tank with steel frame I need help, <Hi Theresa, MacL here with you today.> I'm rebuilding a 100 gallon tank. It has a steel frame, when I took out the old glass, I had to take out some kind of tar. <Theresa that's a very very old tank if I am picturing it correctly and yes it might be something similar to tar.  New glass tanks are put together with silicone instead.> I was told that it has to be hot tanked and NO ONE in Portland does that anymore. <I had to look up to be sure what hot tanked was and here's what I got. "Typically you send it out to be "hot tanked," boiled in caustic soda. This will remove all of the rust. It will also open any impending pinholes if the rust has gone that far. It will also remove any tin coating on the inside which was supposed to prevent rust in the first place." That's for the steel corners of the tank Theresa. And their point is, I'm afraid that they are all concerned your tank is going to leak.> I already have the new glass, and have broke the front panel (have to buy a new piece). What I want to know is there another way to make this tank water tight and not have it pop. <Well I was sitting here thinking about it, what about putting a new tank, or glass pieces inside the old tank. Totally sealed with silicone? You'd have to use all new glass and just set it INSIDE the older tank so you can use the stand and keep the look.>  The glass guy seems to think that I need to get it hot tanked or just buy a new tank. I don't have that kind of money. <I know it gets so expensive.> I have had this tank for at least 15 years, just wanted new glass, already have built a new cabinet stand for it. Please help, is there any other way! <The insert is the only way I can think to go without just totally scrapping the tank Theresa because there is no way to tell how strong the steel is. Good luck and let me know what you decide, MacL> Thank you Theresa

Used Gear Hello to all, <Howdy Gage> just a quick question. I read the section buying used gear, definitely the way to go when working with a budget. I am looking at a 100gal glass tank, 10years old, used only for freshwater, currently housing some cichlids. 10 years seems a little old to me, would you recommend resealing the tank before set up, or "if it ain't broke don't fix it"? remove as much of the old seal as possible then re-seal with aquarium silicone, or just seal over the old stuff? <Mmm, a tough one... I might well re-silicone the inside joints. If there's silicone there (as opposed to just between the glass piece joinings), gingerly (with single edged razor blades held at an angle... to prevent cutting into the joints) remove the old sealant, clean thoroughly with an organic solvent, rub dry with paper towels... and put in a good, new bead... maybe taper/flatten with a tool (tongue depressor, finger...), trimming away excess a day or more later...> Thanks. let me know if I am abusing your kindness by writing too often. I try to find the info on my own first, I read your site religiously. <You, we're doing just fine my friend. Bob Fenner> Thanks, Gage

Tank Repair Hi- I need some help.  I'm a freshwater virgin and I want to do this right (but I'm also incredibly cheap!). <Me too, Home Depot is a great store, and rubber maid makes great containers.> I've acquired a couple of small tanks (10g - 20g) that came with fish (and been given more since) and I want to move them up to larger tanks. <Awesome, the bigger the better.> I've searched the site, but can't seem to find if anyone has had a similar problem.  I have a 30g All-Glass that was drilled for a different filtration system (from a fish room).  I would like to patch this and use an UGF and HOT.  Would sealing the hole on the inside and underside with All-Glass sealant and 1/4" glass be sufficient?  (See photo- hole is in lower left on bottom)  I will be using this as a backup/transfer/nursery tank in a utility room for the convict cichlids that I have right now (the little bunnies that they are). <Someone once wrote in a magazine that convicts would probably breed in a half can of beer.  Love those little guys.  The only sure bet is to replace the entire piece of glass, and that is a pain.  I would use the 1/4" glass and seal it with 100% silicone.  In a tank of this size I would be willing to bet that this would hold.  Let it fully cure and test it outside, and if it blows up, remember that i suggested replacing the whole piece before you get mad at me.> Also, from the same place, I purchased a used 75-80 gallon that does not have a center brace on top- doesn't appear to have ever had one- Should I be worried that it will bow?  The plan is to build a stand and canopy for it- would the canopy be a sufficient brace? <Some tanks are made without the center brace, and will bow a little bit.  Building the canopy with the intent of bracing the tank is not a bad idea, you may never need the brace, but it is better safe than sorry.> I kind of jumped headfirst into this after reading about every FW book in our library.  The fish were "free" (nothing is ever- I know) and so far, I must be doing something right- the only one that died was one of the comets I got for the black shark's dinner! <It can be fun to watch fish munch other fish, but it is not always the healthiest of diets.  That black shark is going to need a much larger tank down the road, if it is a Labeo chrysophekadion it can reach up to 3'!  Best of luck, Gage> Thanks for the help! Shel

This Old Tank  >Hi WWM crew, hope all is good.  >>Well enough, my friend.  >I'm hoping you can help me out, I just bought a 108 gallon Hagen tank {72x18x20} . I got it for a good price but when I was cleaning the calcium off I came across some shortcomings.  >>Used tank, yes?  >First -- The silicone in some spots is lifting along the edge of the seal and I'm worried about leaking.  >>As well you should be.  >Second - There is two small chips on the corner of the tank on the outside, one near the top one near the bottom.  >>If the chips extend into the silicone seal, then this is indeed a problem. If NOT, then a resealing should do the job.  >Third -- The plastic trim has come apart at the corners. Are all these things I should worry about or is this normal for an old tank. The tank is 15 years old and was not used for the last 5 years.  >>Wow, yeah, that's pretty normal. The moulding is protective in nature, but isn't normally relied upon to maintain the integrity of the tank itself. They should be glued together, as the protection they afford round the edges is needed for safety reasons.  >I would have liked to fill it up outside but the ground is soft and I'm afraid it would crack.  >>No concrete pad or patio/driveway area to use? You really MUST fill it in a safe area first.  >I had the help to put it in our bedroom at the time so I took it, it's stupid heavy. Can I slowly fill it and see what happens, my wife is worried it's going to blow apart or something because of the age. It didn't leak when they stopped using it. Any help is good help, great website and thanks. Troy  >>That may be, but the sealant is lifting. At this point my VERY BEST advice to you is to reseal the tank, rather than taking the risk. It is indeed very possibly that it could quite literally burst, but just as bad is any leak, as they never get better. When it gets bad, it gets bad very quickly.  >>I believe we may have tips on resealing posted on site, but if you can't find instructions on how to strip out and reseal a tank let us know and I'll fill you in (I've done literally hundreds). Marina

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