Re: Help repairing 110gal bowfront aquarium  11/6/09 Hello again, Unfortunately after attaching the new top and letting the silicone dry for 30 hours I test filled the tank and found a leak halfway up the side seam. <Uhhh!> The water pressure is bowing the back glass away from the side a tiny bit midway up and causing a leak. From reading your pages it would appear the only correct way to fix the tank is to completely disassemble the tank and reseal it all. <Mmm, maybe not disassemble...> I would love to just seal the leak, but structurally that would be setting me up for a disaster correct? <Too likely to suit> Attached is a picture of the leak. Resealing an entire bowfront tank of this size looks to be a daunting task and not one I am sure I would trust. <Mmm, it's not all that hard... I wouldn't disassemble the pieces of glass. I would cut out the corner beads and clean (see WWM: http://www.wetwebmedia.com/glstksilastic.htm and the others linked above) these areas with a solvent, and reseal (with Black Silastic, 100%) the beads... This really should do it> I purchased the tank used from a very highly respected and strictly reef only store. The store owner swore to me it didn't leak and held water right up to the top pointing to the still visible water line. I assume this is simply what he was told. Do you have any suggestions for how to approach the subject when I talk to him? Thank you, Alex <Show him the pix. There is a possibility that the moving, setting of the tank on a new surface gave rise to this leak. Again, I would not despair. Perhaps ask your dealer if he will help you... with supplying single edged razorblades, solvent costs... the cartridge of Black Silastic... and guidance if you want such. Taking your time here is requisite... Use a tool to smooth out the new Silastic, let cure (a day) and trim the excess... I have done this hundreds of times... Not hard to do. BobF>

Re: Help repairing 110gal bowfront aquarium  11/6/09 Thank you Bob. <Welcome Alex> Cutting and resealing the inside seam I am not afraid of and will try. I think it has already been done once since the top and bottom horizontal seams use clear silicone, and the four vertical seams are black. I was under the dreadful impression that once the structural seal along the edge was compromised a complete reseal was needed. <Mmm, not with a slow leak like this... If it were me/mine, I'd do the inside seams only> If I push the back away from the side it will move about 1/64th inch causing a faster leak. It appears the weak structural area is about 1 inch long in the center of the seam. Your advice is once again appreciated. I will let you know how it turns out. Alex <Please do. BobF>

Leaking 125 gallon tank    02/17/07
My 125 gallon tank has sprung a leak. I have cut out the silicone on the inside on the side it was leaking from.  I resiliconed the seam let it dry  48 hours and began to refill. The tank fills to 2/3 full then begins to leak slowly. I drained tank removed silicon inside tank again cleaned area with  alcohol dried area resiliconed and waited 72 hours for silicon to cure. Refilled  tank and it leaked again when filled a little more than previous time and  started leaking again. Should I reseal tank completely  inside?
<Ah, yes... "at least" this cutting out, cleaning all corners, and re-sealing... As it is not possible to tell where the leak (internally) is actually originating. At the "worst" you may be faced with cutting out all Silastic, dismantling all the glass panels... removing the frame... and re-sealing all... Let's hope not. Bob Fenner>

Possible tank leak??
I think my tank is leaking and now I am concerned. I am losing up to about 3 gallons a day on a 120g at first I thought it was a evaporation thing. Today while filling up the tank I noticed where the doors join when closed salt creep.
<Mmmm, maybe splash or spray...>
I have checked bulkheads all seem fine. The outer edges where I can see where the tank joins from sides to bottom is free of salt. no salt evidence down the seams.
The plywood the tank is sitting on seems dry.... I really do not want to break everything down again,
Suggestions comments welcome,
Lee
<Try taking some toilet tissue and wiping about at all plumbing fittings, joints, seams of the tank... even a small amount of water should show. Do check about for errant spray, splash as well... this "adds up" over time... may come from a pump discharge, mechanical aerator... Bob Fenner>

Possible tank leak
I've read most of your posts about resealing tanks. (great info) I found a post where you actually didn't recommend resealing a tank under 100g because it will leak again in 2 years or so. Do you still feel this way?
<Mmm, in this case "size doesn't matter"... Don't know exactly what the post you're referring to might have been about>
I bought a 75g used from a fish store that went out of business. The tank is 1 year old and it seemed to leak a little so I resealed the inside bottom seam only.
<... best to "do the whole thing." As you now know>
I refilled the tank after 1 week and in a couple of days noticed some moisture underneath the silicone. It wasn't producing a drip on the floor just looked like condensation. Could this just be condensation or is leaking somewhere?
<One or the other...>
Any info or help is greatly appreciated.
Thank you, Mark
<I would at least put a bucket of some sort under the area... and if the occasion presented itself to have the tank dry, clean, empty... cut out the entire inside silicone and replace it. Bob Fenner...>

Commercial Aquarium leak in Ireland
Heh, sorry to send a private message but couldn't find anything on the forums; I think it may be because I need info about a commercial tank and most posts are about private glass tanks.
<No worries. Welcome>
I am a member of staff in a 35 tank native marine aquarium on the west coast of Ireland.  The supervisor recently resigned and left me (completely inexperienced, I was a chef in a previous life) with the task of managing said aquarium. Anyway, I have a large 8 cubic metre tank
<Now, that's a tank!>
that houses conger eels.
<Neat animals... around the world these largish eels can be approached (even handled) with impunity>
  This tank is made of what appears to be concrete with a 2 metre square Acrylic window set about 1 metre off the floor.  A very slow leak has appeared to the right and below the level of the window. I drained the tank and re-siliconed the window panel on all three sides but had a gut feeling the leak had nothing to do with the window.
<Happens>
I could have sworn I saw some kind of suction or movement in the base of the tank when there was a couple of inches left in it.
<Yikes... dangerous>
Now the tank is refilled and conger back in. I think I need to find the location of the leak so I know what I am up against, does anyone know how I might find it?
<This can be a very trying ordeal... as the water can actually originate most anywhere within (or even outside...) the system and appear most anywhere outside... there are some techniques using dyes of differing densities... but I encourage you to go the perhaps expensive route of having a structural engineer firm come in and inspect the system (and all others of size there)... and consider the route of draining, drying, and resurfacing the entire inside (I would remove, clean the race/facing panel, and re-silicone the viewing panel after this) with a water-proof material (likely an epoxy)...>
Some kind of dye? Or is there product I can put into water that will automatically be sucked into the leak? Thanks for any help you can offer
Alex Stewart
Lahinch Seaworld, Ireland
<Oh, see you're aware of the dye... these can be carefully placed in layers (by density) and a spectrophotometer used on the subsequent leak water to detect at which level/depth the water is escaping from... As stated though, I would have the system inspected for structural integrity overall... and re-fit, re-do the entire inside. Bob Fenner>
Lahinchseaworld@eircom.net

Emergency move!  30-gal Tank got a leak
Dear WWM crew:
<Paul>
I never start an email to you guys without thanking you for everything you do... So thanks!
<Welcome>
It seems I am running into bad luck after bad luck starting up my aquarium.  I converted my 30-gal FW to SW and got a 10-gal as a QT tank.  My fish (two clowns, one Gramma, 5 hermits) seemed happy, ate relatively well, and were moderately active.  The Gramma mostly came out of the live rock for feeding, after which he would promptly go hide again.
<Typical. Give it time>
I woke up one morning to find a huge puddle on the floor and a good portion of the aquarium's water level gone!  The aquarium was leaking, so I decided to put everything in my 10-gal.  I filled the bottom with sand, put as much live rock as I could without stacking it while still making caves, filled it with water, and got my fish to safety.  Now, here's where my confusion comes in.
My fish are much more active!  At feeding time, they are extremely anxious to get food, and will even take it out of my hand if I do not let it go in time!  The Gramma no longer spends his time hiding within the live rock.  The crabs are much faster than before.  Is this a bad thing?  Should I take this to mean the fish are happier, or just frantically claustrophobic?
<Something/s are different... maybe you've raised the temperature... perhaps just a good water change...>
I know small aquariums are dangerous because it's harder to keep the water quality consistent.  However, if I have the water tested by a LFS weekly, would it be impossible, and would the fish be unhappy?  
<No store, no agency is able to actually test for all...>
Since I live in a small apartment, the small aquarium looks much better than the large one, the fish are more active, eat better... everything seems to be better, except the actual size of the aquarium.
I have been maintaining this small 10-gal mini-reef like this for the past two months.  I've been changing 25% of the water weekly, and the water I've been taking out of the aquarium, I've been getting tested the same day.  If I am diligent about these parameters, is it possible I may keep the aquarium as is?  Or is it still ridiculously small?
<Mmm, you may have good success for a good long while... much of the probable negative interaction twixt and between the clowns and Gramma has been eliminated through their introduction in the larger tank>
I only ask because my 30-gal is useless, I can't afford a new tank at the moment, and I'd have to give the LFS back all my fish and live rock... and something close to a $500 investment will have been wasted.
Thanks for your time!
Paul Ghica
<Paul... did you actually ever find the leak in the thirty? Very often such "leaks" turn out to be gear failures, splash and spray from a powerhead, diffuser... I would definitely set this tank up (outside) with newspaper under it, and CAREFULLY fill it, check for the actual source (if any)... and even IF it did leak, I would simply reseal (silicone) the inside corners... easy to do. At the very least, sell all to someone who will test, repair it. Bob Fenner>

Marine tank leaking 5+ gallons a day, brackish algae problem
Hi all at Wetweb.
<Craig>
I am not going to beat around the bush I have a major problem. My marine tank started leaking 2 days ago. I am up to 5+ gallons a day.
<Yikes... where from? That is, have you been able to identify the specific region of the actual leak?>
So I set up my spare 55 gallon tank as a marine tank yesterday. I have the temp up to about 78 degrees right now, and salinity matches my other tank. My problem is I have to transfer all 3 of my fish, about 10 crabs, and a whole lot of live rock 50+ lbs, with tons of life on them including some stony coral that just sprouted on the rock over time (I have absolutely no idea what kind they are, two are green and one is cream really pretty). I have to transfer this stuff all today as the mess from the other tank is just too much to live with. In other words no cycle in the new tank. Am I going to have a massive die off, most assuredly the tank they are in now will give out and all will die for sure, if I do nothing. 
<Should work out fine... do vacuum, let settle the water itself in moving... decanter the solids (throw them away)... and carefully re-stack all... upside up!>
What things do I need to do to help the emergency tank change. I am sure you guys have personally experienced tanks that start to leak to the point where they are unusable, any pointers to help me ease the major upheaval in my marine aquarium's life would be greatly appreciated. Also my sand at the bottom of the tank is very full of life I want to use this in addition to the new substrate but I am not sure what to do here. The old sand is more than likely full of phosphates and other icky nasty stuff. How do I clean this without killing everything in the sand or totally polluting my new tank?
<Please read here: http://www.wetwebmedia.com/movingaq.htm  and the Related FAQs (linked, in blue, above)>
By the time you answer this I will probably have made my decision on what to do, as I am doing this today. But how to take care of the substrate for future reference will be nice to know. As this 55 gallon is a bit smaller than the 80 gallon tank I am moving it from, so a new tank move will be in the future.
Now to question number two.  I have a 120 gallon BW tank with a snowflake eel about 20 inches long now, a dragon fish 16-17 inches long, a lot of sail fin mollies (they are proliferate baby makers too), a gourami (odd he is in there and thriving.  Why is he doing so well? I thought he was a freshwater fish only...
<Mmm, can tolerate considerable salt>
...he is a blue common gourami, and he has been in there 3 years now). Anyway my eel eats ghost shrimp and guppies. I have a guppy problem there are millions of them now, this is recent too, and they always seemed to stay about the same in population, way to many for my eel, and gourami to eat. Although they eat a lot of them. I would like to know what BW fish I can put in the tank to cull the guppy population. Salinity is 1.011. I was thinking 3 or 4 figure 8 puffers.
<Better to simply net them out... the puffers will/would likely keep nipping...>
Next one: I have an algae problem too in my 120 gallon tank, never been a problem before. I read on the internet that I could put a Plecostomus (sp) in a BW system. Seems to good to be true. So I was wondering what I could put in the tank that would eat the algae off the rocks and tank glass. 
<You might be able to acclimate (over a period of weeks) a Loricariid species to 1.005 spg or so>
Ok I realize there must be a source of phosphate causing this so I upped my weekly water changes from 15 to 30 gallons and it is not helping. 30 gallons a week is a major job and I do not want to have to keep doing that.  Also I changed how long my lights are on. Thanks in advance for your help.
Craig
<There are other means of algae control. See WWM re. Bob Fenner>

Re: Marine tank leaking 5+ gallons a day
Hi again I did the change and I found the leak in the 80 gallon tank. I was in the right back corner of the tank under the substrate. It was actually cracked. On the bottom glass panel.
<Yikes!>
The tank is now being relegated to the garbage.
<Mmm, might be able to be salvaged... as a paludarium... or patched and partly filled for... turtles, amphibious plants...? I would list it and sell it>
The change went well all things considered, but now I have one more question regarding care of stony corals in a newly set up tank. What kind of husbandry am I going to need to do to keep them alive?
<Same as you've been>
I understand a new tank is hard on stony corals. The tank they came from was set up for about 3 years and really well established. I am using my metal halides with the 55 gallon and other than that I know nothing about corals, as I never intended on having any in the first place. Just a FOWLR tank, as a matter of fact I did nothing to promote them after they started growing. They just do their thing. I leave them alone and they do fine. Now I moved them... So as you can surmise I have none of the equipment to check for proper conditions for coral. All I have is a hydrometer, and a test strip kit for nitrates, nitrite, and ammonia. P.S. I also found a small yellow starfish about the size of a 50 cent piece must have been a hitchhiker and a green crab also about the size of a 50 cent piece, but it has huge claws, it scared me because the thing jumped out of a live rock piece onto my arm, I dropped the rock lol. I think I scared it more than it scared me. I also found several Bristle worms, one about 12 inches which I removed. I kept the small ones. They eat detritus as I understand it, not living stuff. But the strangest thing I found was a little crawdad thing, really bright red about 1 inch long. None of these things I found were consciously put in my tank, but I think it is wonderful how life can survive being taken from the ocean to the distributor, to the pet store to my house. Put into my little slice of the ocean and thrive, then surprise me years later by being seen for the first time. Makes me wonder what else is in the tank, that I still have never seen. Just simply amazing to me.
Craig
<What a planet eh? Please read here: http://www.wetwebmedia.com/marine/inverts/index.htm  re: stinging-celled life care.  Bob Fenner>

Can Not Find the Leak
Hello,
<hi there>
I'm really hoping you can help me out.  I recently added a 6th tank to my collection, it's a 90 gallon that will be a big community tank.  I bought it used, and noticed when picking it up that the guy I bought it from had siliconed the bottom very heavily!  I'm talking likes LOADS of silicone.  His floor behind the tank had serious water damage.  He claimed that his impeller in his Aquaclear 500 broke and it flooded his floor (Sounded like a large lie to me)....
<Mmm, have never heard of such a leak source myself>
After removing the tank from the stand, I noticed that the stand had water damage in the front left and rear right sides, but it looked like the water flowed from the front to the rear right leaving a distinct trail.  I've fixed a 29G before, no big deal, just added a piece of glass to the inside...
<Good technique>  
    So far, me and my father have found ABSOLUTELY no leaks... Yet we both have a gut feeling it's a leaker.  We cut away all the excess silicone, poured water into it and it still didn't leak.  We took notice of the bottom frame looking slightly cracked.  The bottom left corner (where we think the leak is, though can't prove it yet) frame is not flush with itself.  The left side panel also is not flush against the glass, but unless this guy brought the tank to a professional repairer, I don't see how he could've done such a nice job on the sides (the bottom on the other hand was him.. ha)...  The left side is off by maybe 1-2 millimeters, not much, but I noticed it by running my hand down it.  The left backside was perfectly flush, it's just the front left.   
    Sorry for rambling on, here's my questions.. If we can find no leak, should I just believe his "impeller dieing" story?
<I'd believe what you observe>
The side panel not
being totally flush, will that cause any problems?
<Likely not if it hasn't to date>
Should we take the panel out and just redo the whole side?
<I would not>
And finally, is there any easier way to repair a leaking tank, other than totally removing the whole pane of glass you suspect is leaking?  
<Yes... first thing to do is (of course) to figure out IF there is indeed a leak (often equipment, splashing from air stones... is a cause), second, to cut out and replace "corner" silicone, third to affix a panel over a "bad" area and third also... to cut out and replace a panel...>
The 90 uses 1/2" glass and that stuff is massive and seems like it's going to be hard to do much with properly,
<Yes, difficult to remove panels in larger size tanks>
plus, we're still trying to figure out how to make a brace since this tank was made without one and we have glass panel tops!
<I'd consider running two strips (of 3 or 4 inches width) along the inside front and back... or one larger (at least a foot in width) piece in-between the front and back panels at top inside...>
Oh well, this is going to be a big project!  :-)
Thanks for your time guys!
~Joe
<Is the tank in a place that will cause trouble if it does leak? I would place it there full for a week or so to "test the waters". Bob Fenner>

Re: Can Not Find the Leak
Hello Bob,
<Hey Joe>
The tank will be going in my room.  We have a single story ranch with a basement.  The floor is wood, but it now has full carpeting.  We're actually going to just put water in it for 1 week and see how it handles since our last attempt at finding a leak(1 hour ago) led to nothing.
<I'd put it in the basement... or in the driveway>
I spoke to the guy I bought the tank from, he was really serious in saying it was an impeller problem, and that he had no leaks.  Said he siliconed the bottom 2 years ago because a local fish store suggested when a tank hits 5 years old, it be re-siliconed...  He did a really poor job so we will redo it in a more reasonable manner, not just globbing it on...
<Agreed>
And here is a question from my father.  If we do find a leak and the pane of glass does have to be removed, what do you feel is the best way to support the pane once it is put to set back up? He was thinking about making a large frame out of 2x4's for the interior and exterior to keep the pane in place.
<Actually, a few pieces of tape will do... the piece is pretty well stuck in fitting tight with the silicone. Some folks use wood clamps, and if you're going to do a whole bunch of such repairs, jigs can be fashioned, but good masking or strapping tape is fine here.>
  Also, how long should we allow the silicone to set?  The large tube we have suggest 24 hours, but I have heard up to 72 hours.  Which do you suggest?
<I would go with your three days to allow complete curing. Bob Fenner>
~Joe

Re: Can Not Find the Leak
Just thought I'd share with you something related to this persons query.
I have had impeller problems with an older Aquaclear 500... the impeller seized and must have damaged the seal around the motor (or something like that)... when I woke up in the morning about 10% or more of my 230 gallon fresh-water tank had siphoned into the filter, then out of the filter, then onto my floor.  I was worried that it was a leak also (having just bought this tank used) but it really was an impeller problem.
Hope this is useful,
Jeremy
<It has for me. Thank you. Will post. Bob Fenner>

Slow Leak-What Next? Plans for bigger better
Kind Sirs,
<Hello! Ryan this morning>
I arrived home from vacation yesterday to find my 30 gal aquarium had a slow leak. <I'm sorry to hear that> It seems the bottom seal is starting to give way. <Is it an old tank?> I caught it in time, carpet slightly wet, particle board stand pretty much sucked up most of the water and only about a 1/2" of water missing from the tank. <Guardian angel must have been fish-sitting!>
Currently I have a 18 gal Rubbermaid tub filled with tank water and 20 lbs of live rock (aerating), a 5 gal bucket with 2 clowns, feather duster, yellow damsel, and a cleaner shrimp (aerating). I will be moving them to the Rubbermaid later today (wanted to make sure that didn't leak) and a 5 gal bucket with tank water (brown - the 30 gal was a UG setup) and the crushed coral.  My current situation has put me into the express lane to purchase the 75 gal I was researching to set up. <Understandably> It looks as though I'll be going with the 75 gal AGA reef set up with only the one corner overflow. I wanted to look into having a tank drilled, but with my lack of plumbing experience I figured I'd better go with something pre-made. <It's not nearly as imposing once you roll up your sleeves.  I would recommend you look into more- this may be the last tank you buy for some time.  Check out http://www.ozreef.org/ for some great ideas.  Corner overflows can be loud- this may or may not matter to you.>  Future plans will consist of adding a above tank refugium to the sump. <Great!  Ideal>  Many questions on how fast can I upgrade to the 75. Can I get away with adding all the water from the 30 (including the brown) to the 75 and then adding freshly made salt water. (I would like to avoid keeping them in the Rubbermaid while the tank cycles). The new tank will have a 1" sand bed and I will put some of the crushed coral in mesh to provide some bacteria to the sand. Or would I be better off to have a half filled 75 gal and slowly add 10 gal a week over i period of time, using power heads to circulate the tank. Or some possible alterative that you might have. <This really depends on if you're adding more live rock or not.  If you're buying a huge new quantity of live rock, just use the new synthetic saltwater and the rock will cycle it for you.  If you're going to do it slowly, adding pieces of rock gradually, go ahead and dump in the old stuff.  Any way you do it, this is going to recycle.>  As for the 30 gal. It seems the this will become my curing tank for the new rock I will need to purchase. <Possible QT later as well> As for resealing. Can i get away with just adding sealant over the existing or should I look to remove some of the old and put the new sealant over? <If this is never going to be a permanent aquarium again, just patch it.  If you plan on using it, do it right.>  Also, I'm sort of reluctant to turn the heater on attached to the Rubbermaid, should I be concerned with melting (?) or would this be ok? <Should be fine, just watch the temperature very carefully for the first day or so.>  Any thoughts or links to your sight would be much appreciated. Received the new book, only glanced at it quickly, looks great. I was hoping to make it a slow read, now it seems like it's going to be a crash course.  <Dave, this will be fine.  Just keep a close eye on your livestock, and enjoy this experience!  If you're not comfortable with the whole Rubbermaid deal, go get yourself a couple 10 gallon cheap-o tanks.  Take your time!  It's easy to rush it with a new tank, especially if you already have fish in limbo.  There are many similar stories on the FAQs- they should be very helpful.  Good luck! Ryan>
Thanks again,  DaveK

- Leaky Hex -
Hi there!  Well, at 3am this morning I woke to water on the floor.  I have a 65 gallon Hexagon tank.  I could see one of the corners bulging out and water was steady dripping out of it. <Oops... that's no good.> I drained about 2/3 out (not leaking now) and still have my fish in there.  Fresh water.  I have another tank to temporarily hold them, but my question is how to fix the problem?  The tank has been set up for over a year now without a problem and now it leaks.  Is this normal? <No, that's not normal but does happen.> It seems it is only at one joint.  Should I remove the one seal and replace the silicone, and if so, how do you keep the joint together when resealing a hexagon tank? <With the plastic top and bottom, these act as forms when the tank was built.> Is it the same concept as a regular rectangle tank? <Basically, but slightly more of a pain in the butt to assemble because the joints are not 90 degrees.> And if I do one joint, should I do them all? <I would, just because you don't want to go through all this trouble only to have it spring a new leak down the line.>
Thank you for your time!
Christy
<Cheers, J -- >

The leak that fixed itself . . . Huh?
Hello WWM Crew,
I recently picked up a Via Aqua 150 (105 gal.) aquarium from a friend.
It had started leaking at the base and was ruining his new carpet. He gave it to me to get rid of it. I witnessed heavy leakage from the base of the aquarium when I arrived, but it was too wet to tell where it was coming from. After we drained it and lifted it up, there was a bunch of water all over the bottom of the aquarium that had collected between the tank and stand. I took it home. Removed all the sand and let it dry. The next day, I set it on 4X4's and filled it with freshwater up to 2 inches from the top. I didn't notice any leakage so I let it sit overnight.
This morning, there were no signs of leakage. I can't figure it out. The only factors I am considering are that he had salt water in it-which I assume is heavier--and he had a ton of live rock and corral in it--I filled two 25 gallon tubs with rock alone. However, I would think that if the weight of the rock failed the seal that it would still leak once the rock is out, plus I am afraid to put the rock back in because they are in salt water now and I don't want to kill anything by putting them in fresh water. The tank doesn't re-seal itself right? Do you have any idea why I can duplicate the leak and more importantly, what I should do to ensure that the tank doesn't leak again once I get it inside the
house? << Yes, don't fill it with water.  Okay so I know that isn't what you were hoping to hear.  To me, a tank that has once leaked makes a great reptile cage.  I don't like the idea of fixing them and trusting that to be the most expensive thing in my house.  But to answer your question more directly, I would set the tank up again, put paper towels underneath the tank (they work great for finding leaks) and leave it there for several days. >>Thanks for any advise you can give me. << I hope that works. >>
Jeremy
<<  Adam Blundell  >>