Overflow Plumbing

[jeep454]

Hello everyone,
I need some guidance here.
I have a 30G DT with a 10G Sump I have just finished setting up. I was going to use a HOB overflow but have heard horror stories and with my work schedule I DO NOT want to risk a flood. So I will be pulling most of the water out my tank and moving live stock to a container while I drill the bulkhead holes horizontally. (I have confirmed I do not have tempered glass) I already have a 400 GPH pump for return. In a perfect world I would like the overflow to work like this.

Bulkhead -> PVC Elbow -> Ball Valve -> PVC fitting with barbed end -> Tubing to Sump

So the questions would be what size plumbing should I run which would decide my bulkhead size. Also, is it necessary to have an overflow box around this bulkhead. And in regards to the specific fittings I'm looking for I'm having trouble finding them. Any recommendations?

Thank you in advance everyone

 

[Troylee]

3/4” would be plenty for that size tank… your plumbing is normally based off return pump but you have a smaller system so it won’t be much flow..

 

[jeep454]

3/4” would be plenty for that size tank… your plumbing is normally based off return pump but you have a smaller system so it won’t be much flow..

So can I get away with 3/4 overflow and 3/4 return or should I make the return smaller in comparison? And depending on the above answer should I keep the hose sizes the same after the PVC stops? I have a ton of 5/8 hose which is the max nozzle size on the 400gh pump.
Also, any need for an overflow box if I'm drilling into the back of the tank?

 

[Troylee]

So can I get away with 3/4 overflow and 3/4 return or should I make the return smaller in comparison? And depending on the above answer should I keep the hose sizes the same after the PVC stops? I have a ton of 5/8 hose which is the max nozzle size on the 400gh pump.
Also, any need for an overflow box if I'm drilling into the back of the tank?

3/4” for both is fine or use the 5/8” for the return… the purpose of a overflow box is to skim the crud off the top of the water and keep fish and snails out of your plumbing and sump… you could just put a strainer on the bulkhead if you wanted, the only issue is making sure you drill it high enough that when power is cut on the return pump the sump holds enough blow back from the tank.. it would quit draining when the water level hits the bottom of the teeth on the over flow but without it it’s gonna drain to the bottom of the bulkhead which is gonna be a couple gallons more.