From the video: He stresses that he doesnt use any 90's and all 45's, which is great and I'm full believer in this. But yet, he has a T fitting coming off his return pump??? They do have Y fittings, but typically not at Lowes or HD, you have to order them online. I honestly dont think having the return pump in the middle is a good idea. Especially since his returns are not in the middle of the tank. I would put the refugium in the middle and the return on the far right. Honestly though, a refugium of that size really isnt going to help with nutrient reduction, it will only aid in pod population.
What do you plan on keeping in the refugium? And what is the size of your skimmer?