Well I changed everything over to 1" pipe. I had a few issues where the gap between the siphon and stand pipe was restricting the flow, but have that sorted now. She drains really well. Tonight I will silicone the screen pipe to the grow tub, and fill it with media tomorrow. I also need to change my diffuser as we spilled a lot of water on the floor.

Still pending final test.

Just a little good clean fun with fluid dynamics