Corner overflow leak

[Cmarez93]

I recently resealed a large tank I picked up. Took the overflows off and glued them back on. I did a leak test and there is a tiny leak in the bottom corner where the side plastic meets the glass. The leak isn’t on the outside of the tank but that it leaks into the overflow. Would this be a problem since there will be water there anyway? The tank has a Durso style overflow on each side. I thought about slapping an extra layer of silicone over the leak since it is small and figured it would hold. I wanted to see if anyone had any suggestions or if it would be okay as is. Thanks in advance.

 

[pecan2phat]

I would fix this. What will happen during long power outages or if you shut the pump off for an extended time is that the display will drain down till the durso pipe gurgles air. So normally instead of say just below the overflow teeth, it'll keep draining till the durso because the overflow will keep sucking in water from the leak until the durso breaks which could be several inches from the top of the display. You have to have a large sump capacity if this happens.

 

[Cmarez93]

I would fix this. What will happen during long power outages or if you shut the pump off for an extended time is that the display will drain down till the durso pipe gurgles air. So normally instead of say just below the overflow teeth, it'll keep draining till the durso because the overflow will keep sucking in water from the leak until the durso breaks which could be several inches from the top of the display. You have to have a large sump capacity if this happens.

Do you think a patch of silicone would be sufficient or would I need to reseal everything? The sump is 75 gal as well

 

[pecan2phat]

I would say wait for a more experienced reefer to answer that.
Reason is because I don't know if there is a lot of pressure between the display and overflow. My initial guess is not since a lot of manufacturers don't even use glass between the acrylic overflow wall but again I'm no expert.
What I can tell you is that I have had your exact experience with a 100g display. The bottom seal was seeping water. I did nothing for the longest until I drained the tank to move. I did the silicone patch job on the inside of the overflow and I did it sloppy and thick because it didn't bother me what I couldn't see. Eventually the patch job did not hold up and I never fixed it because my return pumps run on a large battery backup and I too use a 75g sump.
Not suggesting to not fix it, but just giving you my experience where I lived with the flaw.

 

[theMeat]

Silicone does not provide a good bond for glass to acrylic

 

[pecan2phat]

We kind of know that but what do you think they use for all those off the shelf Perfecto, Aqueon, All Glass reef ready tanks?

 

[theMeat]

We kind of know that but what do you think they use for all those off the shelf Perfecto, Aqueon, All Glass reef ready tanks?

Umm, they use silicone, which does not provide a good bond

 

[pecan2phat]

Not a good seal but it works, so guessing that it might not be a lot of internal pressure on the wall of the overflow.
What are your thoughts?

 

[theMeat]

My thoughts are seal the holes on bottom of tank, and drill the back for a ghost overflow. If the back glass is not tempered,

If it is tempered on back, the bottom is not since it already has holes drilled, so drill another hole inside each existing overflow and do bean animal plumbing.

One good thing about the silicone is it’s easy to remove the plastic, and it’s likely the plastic flexing that caused the leak. If you put a few dabs of an appropriate, strong enough bond that will hold better, let dry, than silicone to act as a seal works better

 

[Dburr1014]

I recently resealed a large tank I picked up. Took the overflows off and glued them back on. I did a leak test and there is a tiny leak in the bottom corner where the side plastic meets the glass. The leak isn’t on the outside of the tank but that it leaks into the overflow. Would this be a problem since there will be water there anyway? The tank has a Durso style overflow on each side. I thought about slapping an extra layer of silicone over the leak since it is small and figured it would hold. I wanted to see if anyone had any suggestions or if it would be okay as is. Thanks in advance.

If you plan to keep it a durso, I would not worry about the leak. But... I would raise the durso up so the water gets higher in the overflow corner. It will quite the splash over the weir and you won't have to worry about the water lowering in the tank because of the pressure.
Hth