Two hole overflow/drain without a gait valve?

[MoshJosh]

May end up with a pre-drilled tank, two 1” holes in the bottom panel behind an overflow. Think you would normally do a herbie, but hypothetically if you didn’t want to use a gait valve what would that look like? Is running this type of overflow without a gate valve even a thing?

 

[TX_REEF]

Why? Gate valves are ez-pz!

You could, but you'd probably struggle to get it to run silent and you'd definitely want a DC return pump for tuning.

 

[KStatefan]

I do not use a valve on my full siphon. It is designed to flow approximately 400 gph and the balance goes to the secondary drain.

 

[Formulator]

May end up with a pre-drilled tank, two 1” holes in the bottom panel behind an overflow. Think you would normally do a herbie, but hypothetically if you didn’t want to use a gait valve what would that look like? Is running this type of overflow without a gate valve even a thing?

You will want the valve. Without it you can’t fine tune the water height and will either get toilet flush effect where the water cycles up and down or if the water flow through the second pipe is more than a slight trickle, you get the gurgles. I have this setup on my tank and these sounds are extremely annoying. My gate valve is a must. Not to mention you will need a pretty extreme return pump flow rate just to achieve full siphon on a 1” drain. I have a large external iwaki return pump and can’t achieve full siphon unless the gate valve is partially closed, though my sump is in the basement so have the large head pressure to overcome.

 

[mfinn]

May end up with a pre-drilled tank, two 1” holes in the bottom panel behind an overflow. Think you would normally do a herbie, but hypothetically if you didn’t want to use a gait valve what would that look like? Is running this type of overflow without a gate valve even a thing?

I'm sure there are some that manage to get that perfect balance between drain and return pump that is quiet, but why go through the drama. Just do the gate valve in the build. If you some reason you don't want to use it, go with it wide open.