Help! Center brace fallen off 250 reef tank, major issue?

[Hendrix99]

Woke up to find the glass center brace fallen into my 8 foot 240 gallon tank (it was a used custom tank that has been setup and running for 2 weeks now. Have 2 mp 60s and a heavy canopy on it as maybe likely culprits. So far side seams are not leaking but am I looking at a imminent failure and should drain it or can I attempt repair?

 

[dave.m]

How old is the tank? If it is older than 8 years it is possible that the rest of the silicone may be ready to go, too. Obviously the safe thing to do would be to drain the tank, replace all the silicone, and start over.

On the other hand, if the tank is not too old, it is possible that only the silicone at the top has been prematurely aged by exposure to heat-intensive lamps, in which case it would be safe to simply re-silicone the brace back in place.

Well, are ya feelin' lucky?

Dave.M

 

[pmcarbrey]

How old is the tank? If it is older than 8 years it is possible that the rest of the silicone may be ready to go, too. Obviously the safe thing to do would be to drain the tank, replace all the silicone, and start over.

On the other hand, if the tank is not too old, it is possible that only the silicone at the top has been prematurely aged by exposure to heat-intensive lamps, in which case it would be safe to simply re-silicone the brace back in place.

Well, are ya feelin' lucky?

Dave.M

+1

Also, if you wanted, its possible to eurobrace a filled tank. its a PITA, but its possible, you just have to be careful. what I'd do is take the time to reach inside and actually feel the seals; if the silicone is hard and/or peeling, time to replace. If the seals still have that rubbery feel to them and do not have and tears/peeling sections I'd go ahead and take a longggg level and check the front and back pane of my tank, if there is significant bowing, drain 50-70% of water and check again, this SHOULD fix the bowing. if you check again and the bowing is not fixed, drain the tank completely, you've got a lot of work to do! If the bowing is fixed, take this opportunity to replace the brace or insert a new one.

I've had to do this three times on three different tanks, only one of them required a complete tear down (~1.5" bowing on a 4ft pane when empty)

 

[Hendrix99]

Ha! Not feeling so lucky right now except for the fact I did not have a full blow out. Not sure how old the tank is as it was through a used tank dealer however the seams on the side of the tank seem rubbery and are not peeling at all. Tank was bowed a good inch judging by the distance form the center brace as a guide. I have drained a little mor than half of the tank and the bowing is down to about a 1/4 inch from the brace (placing the brace all the way at the back glass and measuring the gap to the front. How much of a gap should here be and should I scrap the tank (due to the stress placed on it),attempt the brace repair (do you use clamps to hold it in place and what would be the chance of it failing again based on the tanks you have done this to) or something else?

 

[pmcarbrey]

Ha! Not feeling so lucky right now except for the fact I did not have a full blow out. Not sure how old the tank is as it was through a used tank dealer however the seams on the side of the tank seem rubbery and are not peeling at all. Tank was bowed a good inch judging by the distance form the center brace as a guide. I have drained a little mor than half of the tank and the bowing is down to about a 1/4 inch from the brace (placing the brace all the way at the back glass and measuring the gap to the front. How much of a gap should here be and should I scrap the tank (due to the stress placed on it),attempt the brace repair (do you use clamps to hold it in place and what would be the chance of it failing again based on the tanks you have done this to) or something else?

if it's down to a quarter inch you should be fine, clamp and replace the seal, you should be fine. I've never had a tank that i've redone fail on me, but then again, I am rather.... liberal, with my silicone usage and usually put a 2" eurobrace along with a center brace (essentially the same style you see on the larger acrylic tanks).

what are your plans? to replace the rim (assuming it's a glass tank) or just redo a brace?

 

[Hendrix99]

Well if it can be fixed I was thinking about just replacing the seal and just siliconing the hell out of it but if you think it's needs to be euro braced I'd be open to trying it. Did you let the silicone dry 48 hours or longer and did you keep livestock it at the time?

 

[pmcarbrey]

Well if it can be fixed I was thinking about just replacing the seal and just siliconing the hell out of it but if you think it's needs to be euro braced I'd be open to trying it. Did you let the silicone dry 48 hours or longer and did you keep livestock it at the time?

I let it dry for 24 hours, replacing the seal would work fine, it really comes down to personal preference. I kept livestock in and just made sure not to drip anything into the water.

 

[dave.m]

At eight feet long and only one centre brace with no eurobracing I think you are dancing with death. No wonder the existing brace popped and you've got an inch deflection. If you're not going to put eurobracing along the whole length I would go with three evenly spaced eurobraces, not just one. Better safe than sorry.

Dave.M

 

[Hendrix99]

Hi Dave, what size euro bracing would you put and how is it placed in regards to the center brace?

 

[Hendrix99]

FYI the center brace is 1/2 inch thick glass and 9 1/4 inch wide if that makes a difference

 

[dave.m]

Oops! Sorry, that last point should have said three centre braces. What are the dimensions of your tank (L x W x T)? What is the thickness of the existing glass? e.g. if it is all ½" glass then use the same. At eight feet long I would go with three six inch wide braces evenly spaced. Trying to do it all with one extra wide brace is not enough, as you have seen.

To make it even beefier, I would have added centre braces at the bottom of the tank, too, but you say you have already filled the tank so it is a bit late for that.

Dave.M

 

[Hendrix99]

Hi Dave the tank is 96 x 25 x 24 inches and the glass is 1/2 inch all around. Since I already have the 9 1/4 center piece would it make sense to use that in the center and then add 2 6 inch wide ones? Additionally when you say evenly spaced I couldn't center the large piece and then place the 2 at the edges? Incidentally I have a local tank builder who might come by and take a look who also agreed one center brace wasn't going to cut it, but instead suggests a custom canopy that would brace the whole top. Have you ever heard of external bracing like this and would it work?

 

[dave.m]

Yes, I have seen rim braces made of powder-coated angle iron (make sure it's made of SS-216 or above). I have also seen a sort of bar clamp and even a cable clamp. I have never been involved in using clamps or their design.

For such a long span (96") I would still go for equal spacing rather than at the ends but that's just an opinion.

Dave.M

 

[Hendrix99]

Ok I think I might go with the 3 center braces but not quite equal spacing (the overflow would interfere, would them not being equal cause a problem?) Do you clamp the tank till it's flush distance to the center brace width (or ahould the distance be larger) then silicone and hold in place via tape or other method? Are 2 clamps sufficient and should they have wood in between them and the glass?

 

[dave.m]

Equal spacing: whatever works for your tank set-up
Clamps: yes, but use the clamps to hold the braces in place while siliconing
Flush: yes, bring it close to the existing brace's length, but leave at least 1/16" for silicone on each end of braces - don't squeeze all the silicone out of the joins
Curing: I would clamp the braces in place while the silicone cures - N.B. do all of them at once, not one at a time
Padding: yes, I would pad the clamps, especially if they are metal, to protect the glass from any scratches or scoring

Make sure to use an aquarium-safe silicone, i.e. no mildewcides, etc.

Dave.M

 

[kevin kaplan]

I also have this problem on my 240 gallon where the center glass/brace broke when I did a water change. The water level went down, the glass got too hot and I left too much time before I filled it back up. When the water level came back up to the glass, the thick glass/brace broke. the tank is slightly bowed, but it has been going for 2 yrs since this happened. Fingers crossed until next year when I move and change tanks. Advice: look down your tank from the side and see if it is bowed and that may tell you how pressing it is and if you need to get a new one or fix it.

 

[Hendrix99]

Thanks, the bowing was over an inch until I drained it to half level. Thanks for all of your help Dave M., just got the custom cuts of glass, will do the 2 6 inch pieces and a new 9 1/4 piece in the center. One last question, how much force should the clamps have? There is quite a bit of cost difference between the 600 pound 36 inch clamps and 40 or 50 inch 1,500 pound ones. Would the 36 inch be sufficient and would I be best using 3 (one for each brace location?)

 

[dave.m]

One per brace. The lesser strength clamp is fine. Remember not to squeeze all the silicone out of the join or you will have accomplished nothing. There really shouldn't be much of any load on the clamps. They are there to hold the the side panes to the braces long enough for the silicone to set. It wouldn't hurt to put something under the braces to keep them level while you set up and the silicone cures.

Dave.M

 

[Hendrix99]

I went ahead and did the repair last night, the one thing I was concerned with is that I was unable to get duct tape to help support the braces in addition to the clamps so I had to tighten the clamps until they held the braces in places (otherwise the brace would slide). After that I did run another bead on the top and bottom. This distance appears close to being exactly flush. Would you say that is normal or is that what you were referring to in terms of pushing all the silicone out?

 

[dave.m]

Yes, it is probably too close. That's why I suggested supporting the braces from underneath; some 2x4s, a Kleenex box, whatever. If they pop again you will at least be an experienced aquarium repair person and can deal with it yourself.

Dave.M