however many penguin350s you were planning to get (3?), replace them with AC70s instead. they are better filters in every single way, and you will never have to buy an expensive replacement cartridge.
overflow diagram:
overflow explaination:
flowrate for pipe sizes:
size _GPM __GPH
1/2 = 2.50 = 150
3/4 = 5.63 = 337.5
1.0 = 10.0 = 600
1.25=15.6 = 937.5
1.5 = 22.5 = 1350
2.0 = 40.0 = 2400
example of a finished overflow:
(in these pics, the check valve was not yet installed, but as seen in the diagram above, it is a vital part of the system. you can not run one without it. )