sump set up

[4dog]

I am setting up a sump for my 125 gallon acrylic turtle tank. I have made and installed an internal overflow box and need to drill and install bulkheads. I have a 1325 gpm pump and need to know how large my primary drain back to the sump should be. I would like to use a 1", but is that big enough? I am planning to add a 1 1/2" secondary drain line in case the primary gets clogged. Should I go with an 1 1/2" primary or is that too big to achieve a full siphon? I will add a ball valve on the primary to achieve this. help!

 

[Brandon4432]

I would go with 1 1/2. Always better to be safeeeeee