Drain Experts Please Read

[kris4647]

I'm wondering what the total maximum flow is through a
1" bulkhead drain......

I have two and I'm planning to run an AM3k on my return...Any thoughts..Similar set/ups

Would it increase total flow if I increased pipe diameter before and after the bulkhead? [I'd like to use Durso's in the overflows]
I realize I'm limited by the 1" in the bulkhead........


Any help would be appreciated. I do also realize that there is a relationship with overflow teeth spacing and total throughput possible. I have a 215 Oceanic RR. I did not special order so it came however they normally manufacture/plumb them ...

Thanks Kris

[kris4647]

Also can anyone explain this portion of the drain calculator



"Recommended minimum linear overflow size = xx inches "

[gregt]

I'm wondering what the total maximum flow is through a
1" bulkhead drain......

It depends on the water pressure behind the drain, and how much noise you are willing to live with. The calculator tries to give a "best results" number.

I have two and I'm planning to run an AM3k on my return...Any thoughts..Similar set/ups
Two 1" drains won't handle the 3k if it's on full blast.

Would it increase total flow if I increased pipe diameter before and after the bulkhead? [I'd like to use Durso's in the overflows]
I realize I'm limited by the 1" in the bulkhead........

Yes, that will help some, but probably not enough to handle the ampmaster at full force.

I do also realize that there is a relationship with overflow teeth spacing and total throughput possible.

"Recommended minimum linear overflow size = xx inches "

In a few days the latest edition of reefkeeping will have an article that goes into detail on both these items....

[Dimi-reef]

Rule of thumb that I have seen...and use is as follows

1" 600-800 gph depending on how much water (size) the teeth let pass thru on the overflow box

2- 1' is 1400 gph

1.5" 1600 gph

Hope this is what you are looking for.

My tank has a single 1.5" to the sump and my return is an Ampmaster 3000 ...which is plumbed with 1.5" reduced at the 3 3/4" sea swirls and I have to cut back the flow because the Ampmaster out pumps what the bulk head is capable of.

[kris4647]

That exactly the type of info I was looking for thanks ....

I'd like to hear some more drain setups with Ampmasters if anyone else would care to chime in

Thanks to Everyone..........

[drscheck]

You will always be limited in how much flow you can have by the smallest diameter. Increasing pipe diameter before and after the bulkhead will not increase the amount of flow through the bulkhead.

Dimi-Reef's numbers are reasonable, of course the amount of head pressure on the hole will increase or decrease the flow through the hole.

If you put Durso's on the bulkhead, so are effectively reducing the head pressure on the drain by the height of the Durso.

For example if you have a 30" tank with no Durso, you would have 30" of head pressure on your drain. If you install a 28" Durso, you have reduced your head pressure by 28" and are essentially running 2" of head pressure on your drain.

So a 1" opening beneath 30" of water can discharge 30 gpm or 1800 gph, but if you put in a 28" Durso, your opening is effectively under 2" of water and the rate is 7.8 gpm or 468 gph...of course these calculation assume you are discharging the tank through the hole alone, as soon as you start putting plumbing on the hole you start getting back pressure and frictional lose.

MY rule of thumb is 700gph for a 1" hole

Hope this helps.