rate of flow under gravity

[Silent Night]

i have read too many differing opinions on the net regarding bulkhead flow rates, so before i a drill 1" hole in my new 135 gal and screw it up... can someone please verify this for me:

rate of flow under gravity in a 1" bulkhead

3/4" - 300 gph
1" - 600 to 700
1.5" - 1400 to 1600

?

 

[David S]

use this site but its US gallons
or

3/4" =660 US 550 UK
1" =960 US 799 UK
1 1/2" = 1500 US 1250 UK

There's not too many english people on this forum so remember most gallons are American

 

[Silent Night]

Thanks David!