Best way to move a bulkhead to a new location

[IronMan72]

I recently picked up a 180G system that included an acrylic sump. I need to move a couple of the bulkheads that come out of the side of the sump and move them to the bottom. If they are left where they are they will be sticking out into an area that people walk and will eventually get bumped, cracking the wall of the sump.

So... How do I plug the existing holes?

Options I've considered for plugging the existing holes.
1. Do they sell hole plugs that can be mounted in place of a bulkhead?
2. The flange side of the bulkhead is threaded so I could just get screw in plugs and cut the bulkhead short.
3. Cut a square of acrylic and mount it over the hole.
4. Sell the sump and buy the acrylic to build a new one. (Last Resort)

Any other ideas?

 

[Capt_Cully]

Is there room inside the sump if you simply pull them out and stick them back in the other way around? Then you can thread something in and plug it without it sticking out into a walking area.

Make sense?
Feasible?

 

[pascal32]

Marks thought is probably the easiest. If you decide to remove the bulkhead and cover with a pies of acrylic on the inside make sure to talk to someone who knows acrylic. I beloved you would need to use acrylic glue which fuses the two surfaces together- in other words don't use silicone!

 

[pascal32]

Odis the opposite with a reefready tank that was converted to a sump, covered the bottom holes with glass (glass tank) and drilled the side. It's been working great!

 

[belgian_waffleman]

Option 3 will be the best. Make sure you use acrylic cement, glue from the inside so water pushes against it.
Like Pascal said, do not use silicone, and talk to someone who knows acrylic as there are many different acrylic cements out there.

Good luck with the new tank!

Waffleman

 

[IronMan72]

Is there room inside the sump if you simply pull them out and stick them back in the other way around? Then you can thread something in and plug it without it sticking out into a walking area.

This would work and I considered doing it this way but I read an application note somewhere that said it was bad practice, and not recommended to mount a bulkhead with the flange on the outside. It did suggest that it could be done, just not recommended. I think it was because the gasket would be on the outside and if the gasket were used on the thread side that the rotation of the nut while tightening could compromise the gasket. If it is "ok" to do then maybe I will. I could just cut the nut side of the bulkhead short and do exactly as you suggested with the flange pointing in though. Either way, the bulkhead will be useless because there isn't enough pipe between fittings to connect a new fitting.

Option 3 will be the best. Make sure you use acrylic cement, glue from the inside so water pushes against it.
Like Pascal said, do not use silicone, and talk to someone who knows acrylic as there are many different acrylic cements out there.

Good luck with the new tank!
Waffleman

Good advice, I would use acrylic adhesive if this is the best option.

 

[pascal32]

The reversed bulkhead requires the rubber seal to stay on the flange side. It serves little value on the thread side as it will seal the nut to the tank, but allow water via the threads.

As far as whether it seals better with the flange inside or outside I have no idea.

 

[IronMan72]

The reversed bulkhead requires the rubber seal to stay on the flange side. It serves little value on the thread side as it will seal the nut to the tank, but allow water via the threads.

As far as whether it seals better with the flange inside or outside I have no idea.

Aha, makes perfect sense, just didn't remember the reason. Still not sure why gasket on the outside is not recommended but after cutting the threads short there won't be much more sticking out than reversing it.

Sounds like a threaded plug might be the easiest solution and patching over the hole with acrylic is probably the best. I have never done any acrylic welding so I can see where I could easily make matters worse if I messed it up. Can anyone elaborate on how I could screw up the threaded plug method?