What are the effects of bringing drain line in under water?

[Anonymous]

I am eventually going to turn my 75G reef into the refugium of my new 300G tank.

I just spotted a potential problem with this. The extra tall sump I have for my 300 will have a running level that is higher than the bottom of my 75G. Raising the 75 just so that the drain would work would suck.

I have an extra 1.5" bulkhead at about 6" from bottom of the sump. I would have no problem running a drain from the 75 to that bulkhead. That bulkhead would be about a foot and half below the running water level of the sump. Would that prevent the drain from working properly?

I don't need a tremendous amount of flow through the 75 since it is going to be a fuge.

Louey

 

[fungia]

hmm. it should work fine. if the drain from the 75g is taller then the top of the sump then i dont see why there is any problem, gravity will still do what it is suppose to do, right?

 

[Anonymous]

As long as the fuge is higher than the sump it will drain. have you considered have the fuge dump straight into the tank?

 

[Anonymous]

I shoud sat this differently. If the water level in the 75 is higher than the water level in the sump it will drain. Make sure the top of the 75 is higher thn the sump in case of power failure.

 

[Anonymous]

The top of the 75 is well taller than the the top of the sump. But the drain comes out of the bottom of the 75 which is lower than the top of the sump. So I will take the drain to the bulkhead at the bottom of the sump.

I was wondering if the backpressure from the water in the sump would somehow restrict the flow coming in from the 75G? There will be a hundred or so gallons of water in the sump above the bulkhead that I want to come in though.

Louey

 

[Anonymous]

It should not be a problem. What will be the water level over the inlet to the sump?

 

[Anonymous]

The water level in the sump above the inlet (bulkhead) is about 1.5 foot above the inlet.