External overflow question

[Formulator]

I’m building out a small frag farm that I will tie into my existing system. Been in the hobby for almost 10 years, but have always had an internal overflow drilled through the bottom. I’m placing this aquarium on a small wet-bar counter in the finished area of my basement, adjacent to the unfinished sump room that I will tie into.

My idea was to avoid drilling through the countertop by using an external overflow, but I goofed the measurements and the box won’t fit between the wall and tank. My question is: is the external box necessary for anything other than creating depth for siphon? If I used a large diameter PVC drain pipe that could handle the flow without siphon, and I’m not concerned about noise, can I run the drain pipes directly from the tank’s bulkhead?

Thinking I could fit a 90 degree joint and 2 inch PVC for a short run into the sump to the left of the wall there…

Also open to any other creative ideas. Don’t really want to cut into that wallpapered wall if I can avoid it.

 

[tbrown]

Yes.

You can actually install a weir box inside the tank that would function basically the same. Without the box/weirs, the water level will drop to the bottom of the bulkheads. With weirs, the water level in the display will drain to the weirs and only the weir box will drain below the bulkheads.

 

[Formulator]

Yes.

You can actually install a weir box inside the tank that would function basically the same. Without the box/weirs, the water level will drop to the bottom of the bulkheads. With weirs, the water level in the display will drain to the weirs and only the weir box will drain below the bulkheads.

Awesome. It actually came with the internal weir box so I can just delete the outer box and should be in good shape.

Thanks for your help!

 

[Dogeatbird]

Another solution is to use a 90 elbow as the internal weir, with a tee as the external weir. By indexing the elbow position, you can passively set the display height, with surface skim. When the elbow is placed at the six o’clock position a full siphon can be generated. Max water flow is never the full potential of the pipe diameter, please bear that in mind.

 

[Formulator]

Another solution is to use a 90 elbow as the internal weir, with a tee as the external weir. By indexing the elbow position, you can passively set the display height, with surface skim. When the elbow is placed at the six o’clock position a full siphon can be generated. Max water flow is never the full potential of the pipe diameter, please bear that in mind.

Thank you for this! Very interesting. This project is still on my to-do list so I may try both methods. I’ll report back with results…

 

[Daniel@R2R]

Definitely let us know how you end up working this out