Two things on your plumbing. You need to ditch the copper barbed fitting on your return and replace it with a PVC fitting. Bulk reef supplies has any and ever thing you need if your local hardware doesn't have what you need. I would also recommend adding a quick disconnect to your overflow line as well and get some plastic hose clamps for all of your tubing connections to prevent leaks as you will have them with out the clamps. BRS also carries them.
Thanks Tbabcock. I am getting rid of it, this is just for testing my build while the PVC piece gets here. And I do have clamps for all the hoses, I will put them on after I glue everything. What do you mean by adding a quick disconnect? adding a union to the overflow line?