Drilling Return Holes

You will need to have return bulkheads in your aquarium for the return pump to flow water back into your aquarium. To drill these you will need the following.

• 3/4" SLP X FPT Bulkhead https://synergyreef.com/product/3-4_bulkhead-fpt-slp/

• 35mm Diamond Holesaw Bit https://synergyreef.com/product/35mm-diamond-holesaw-bit/

Follow the Drilling Your Aquarium instructions for the drilling procedure.

Where you install them is up to you, but we recommend about 2" below the top of the aquarium.