Bulkhead Flow Rates?
- Thread starter logan15
- Start date
squidd
Active Member
Originally posted by Kip4130
1" will run about 700 gph if drained thru the tank bottom
.. will run about 500gph if drained out the side wall of a tank or via hang on overflow
I beg to differ but I'm getting 700gph+ out of my 1" HOB overflow with Durso pipe...
Head Loss Calculator
Vertical length in feet 4
Horizontal length in feet 1
Pipe diameter in inches 0.75
Choose your pump: Mag12
Number of 90 degree elbows 2
Number of 45 degree elbows 0
Number of gate valves 0
Number of ball valves 0
Number of union couplings 0
Number of swing check valves 0
Number of pipe exits 1
Number of pipe entrances 1
Total losses are 8.74 feet of head pressure, or 3.78 PSI. with a flow rate of 717 GPH. Process took 57 iterations.
(I just put the Mag on yestrday to test it out, will be going back to the 600gph I had before. Pump is for a different tank and setup.)
squidd
Active Member
I don't have any "teeth" on the inner box of my overflow...5 1/2' X 2 1/2" box, water only over the front, runs about 1/4" to 3/8" over "lip"...I did have to go to 2 of the 1 1/8" "U" tubes and 1 of the 1" "U" tubes to get water over the top, to the outer box...My "Durso" style tube will suck the outer box "dry" (till it sucks air) if I don't regulate it with an air valve.
I know the 3/4" return line is small for a Mag 12 (like I say I was only testing it) But 4' vertical with 2 90s on a Mag 12 gotta be 700+
I run all my "calcs" on the conservative side...I could do the "bucket test" to confirm...
I agree though, you definitely want the overflow capable of taking out more than the pump can put in...
That is a full 3/4" ID (more like 7/8") thin wall PVC pipe, by the way.
I know the 3/4" return line is small for a Mag 12 (like I say I was only testing it) But 4' vertical with 2 90s on a Mag 12 gotta be 700+
I run all my "calcs" on the conservative side...I could do the "bucket test" to confirm...
I agree though, you definitely want the overflow capable of taking out more than the pump can put in...
That is a full 3/4" ID (more like 7/8") thin wall PVC pipe, by the way.
golfish
Active Member
Originally posted by logan15
maybe top of tank i havent decided if i want to get built in overflows or not
If you were to use a 1" bulkhead drilled at the topside of the tank you might get 100 gph through it..(been there, done that) if you drilled it at the bottom and used a standpipe you'll get around 600-800 gals but you'll be asking for trouble. If you use a built in overflow you'll still get the 600-800 but you'll be safer.
HOB's are almost as safe and as good. If setup right they can probably do close to the GPH as a built in..
Do yourself a big favore and use OVERFLOWS..If you don't I guarantee you'll be sorry.
golfish
Active Member
Originally posted by Kip4130
man... thats not being very optimistic
i have 3 1" thru the wall bulkheads on various tanks... and they all give me about 500gph
I can see close to 500 gph with all three . I did it with a 25 gal fuge next to the old 150, no elbows just a long swing with 1" spa flex using a MJ1200 for a return. I had to run the MJ on a float switch because the flow rate was so close...what do ya think a MJ1200 would do with about 4 feet of head?