Leak into overflow box.

radav88

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Good afternoon! I am finally getting water in my tank ( I received it last October). Last weekend I started the process of filling the 150 gallon tank with water. I got it filled to the point to the point where water had reached the bulkheads that connect the internal overflow to the external overflow box. Walked away to continue making more RO/DI water and came back in the morning to water in the sump and noticed that one bulkhead had a very slow leak that was draining into the overflow box. So I drained the tank back down below the bulkheads. Went to take off the unions of the three drain pipes and two of the three are stuck to the point I can't get them off. So rolling with the punches I had my wife unscrew the bulkheads while I hold up the rather heavy overflow + piping. She dried off the gaskets, glass, and we also peeled away the black stuff the builder applied to that end of the tank. Reseated everything, tightened up the gaskets, and filled up again. Pretty bad leak out of one bulkhead. I am on attempt number three of doing this and after it sat there with no leak for about 30 minutes two very slow leaks appeared at both bulkheads going into the overflow. Today I applied some food grade silicone grease to the gaskets before we reseated everything. I tightened the bulkhead nut hand tight as much as I could possibly turn it and to my dismay still a slow leak.

So here are my questions. How much should I try to tighten down the bulkhead nut once I have it as far as I can hand tighten it. I'm very wary of attempting to use a wrench for fear I will crack the tank. Should I let everything sit for like 24 hours after I have tightened things down before attempting to fill again with water? Is it possible that the weight of the overflow and all this plumbing is slowly causing things to shift slightly? How do people support the weight of the pipes? I see all these pictures of people's clean plumbing setups and never see any sign of supports for their plumbing. If I absolutely have to get the unions off to make working with this more manageable, since hitting them with a mallet is not feasible does anyone have any suggestions for how I can get them unstuck? Any suggestions would be very much appreciated.
 
Would get new bulkheads and start from there. Would clean both sides of glass with razor, and be sure to put rubber washer on the inside. Hand tighten, then maybe 1/4 turn
 
Yes hand tighten but not as tight as you can get it by hand. Once you get to the point of the gasket making contact then 1/4 turn more. Over tightening causes more leaks then not tight at all.
 
Yes hand tighten but not as tight as you can get it by hand. Once you get to the point of the gasket making contact then 1/4 turn more. Over tightening causes more leaks then not tight at all.
I will definitely try this. Given your description I have been over tightening for sure.
 
Also make sure your Bulkhead nuts will screw all the way down, before installing them on the Aquarium. I’ve seen poor quality there, and they aren’t threaded all the way. Teflon tape on the bulkhead threads, for the nut, will help also.
 
The water is supposed to go into the overflow, your bulkheads are fine. The connection from the internal box to the overflow is bad, or the internal box has a leak below the weir.
 
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Another thing, make sure you lube rubber gaskets/o-rings with silicone grease and not vaseline. Vaseline will cause the rubber to swell and deteriorate.
 
Another thing, make sure you lube rubber gaskets/o-rings with silicone grease and not vaseline. Vaseline will cause the rubber to swell and deteriorate.
Yeah I used dow 111, which is a food grade silicone O-ring lubricant.
 
Quick update. Ive attempted to fix this issue a few times since I posted. Ive messed with how tight I make the nut, Ive thoroughly cleaned the glass, and applied a very thin layer of silicone grease to the gasket and I'm still getting a leak from one or both bulkheads into the overflow. I've gotten it so it's exceptionally slow but if the power goes out I could end up with an oveflowing sump, plus I also dont trust that the leak won't get worse over time.

One thing I did notice was that the gaskets included with the overflow have a circumference that is ever so slightly smaller than the hole my builder cut (to the overflow makers spec) or the hole cut into the gasket isn't perfectly circular so when it sits on the glass there is a bit of an overhang of material on one edge. Could this be the issue? I'm kind of at a loss here for how to proceed, especially if the new gaskets/bulkheads don't work.
 
Another thing to check is to make sure the gasket is where the manufacturer recommends. It is not always on the inside of the tank. For my modular marine ghost overflow the O-ring actually goes between the outside of the tank and the outside plumbing box.
 
Another thing to check is to make sure the gasket is where the manufacturer recommends. It is not always on the inside of the tank. For my modular marine ghost overflow the O-ring actually goes between the outside of the tank and the outside plumbing box.
So this is actually a modular marine overflow. I do have the gaskets in the correct spot just like you mentioned.

To answer your other question I found the overflow was leaking into the external overflow box because I was preparing to test the whole plumbing setup and noticed water in the overflow when it shouldn't be as I was filling thr tank. That's when I saw a slow drip from the bottom of the bulkhead nut on the inside of the box. So I haven't even turned the return pump on yet.
 
Go to 2:10 on this video

Is it leaking from where the bulkhead touches the glass? Or is it leaking from where the internal box attaches to the bulkhead?

Is there any water on the floor?
 
Do you have the internal box installed?
Yes the entire overflow is installed. Internal box connected to external.
Go to 2:10 on this video

Is it leaking from where the bulkhead touches the glass? Or is it leaking from where the internal box attaches to the bulkhead?

Is there any water on the floor?
No water ended up on the floor. I was there as the leak started.

Water is leaking into the external box from a drip that appears at the bottom of the bulkhead nut.

When I put this together I hold the internal box flush against the inner wall of the tank then screw on the outer box. Everything looks to be seated well but I still get a leak.
 
Quick update. Ive attempted to fix this issue a few times since I posted. Ive messed with how tight I make the nut, Ive thoroughly cleaned the glass, and applied a very thin layer of silicone grease to the gasket and I'm still getting a leak from one or both bulkheads into the overflow. I've gotten it so it's exceptionally slow but if the power goes out I could end up with an oveflowing sump, plus I also dont trust that the leak won't get worse over time.

One thing I did notice was that the gaskets included with the overflow have a circumference that is ever so slightly smaller than the hole my builder cut (to the overflow makers spec) or the hole cut into the gasket isn't perfectly circular so when it sits on the glass there is a bit of an overhang of material on one edge. Could this be the issue? I'm kind of at a loss here for how to proceed, especially if the new gaskets/bulkheads don't work.
I think this is the issue. The gasket is just too small and any little shift in it while installing is creating a spot for water to seep through.

I would either 1) just go get some gasket material from a hardware store and make a new one. Or 2) just use some silicone. Put a nice bead of silicone on the flange of the bulkhead and install it, then put a slight bead around each and smooth it out.

Personally I would go with silicone to seal it in place.
 
I think this is the issue. The gasket is just too small and any little shift in it while installing is creating a spot for water to seep through.

I would either 1) just go get some gasket material from a hardware store and make a new one. Or 2) just use some silicone. Put a nice bead of silicone on the flange of the bulkhead and install it, then put a slight bead around each and smooth it out.

Personally I would go with silicone to seal it in place.

Thank you, I'll definitely try to make the new gaskets so they fit properly around the hole and I'll keep the idea of sealing with silicone in my back pocket as a last resort.
 

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