Nevin's 14G + 5.5G sump

[Nevin]

Finally, saltwater in the tank! I ripped apart the return plumbing and redid it. Much better now with no leaks. The only issue is the swing check valve--when I cut power to the return pump the flap in the valve jitters back and forth making a loud noise and allowing a significant amount of water through before closing. It also allows a trickle of water through when closed. I think I've read that they're adjustable--would I just tighten the screw(s) holding the flap to make it close quicker? Here is the valve I have:

3/4 true union swing check valve

Otherwise I'll have to lower the sump water level, put some plumbing on the return inside the tank to prevent syphon, put an aqualifter on battery backup to compensate or all of the above... I don't want to be too dependent on the check valve but there aren't a lot of other options.

I have put some of my existing live rock and sand, plus some new sand in the tank and will allow to cycle as I'm going out of town for a few days. I don't expect there will be much of a cycle just transferring from the old tank to the new one, will there?

Pictures follow and see my old 10G thread for new pictures as well.

Leak test:


Plumbing:


Cycling:


Any suggestions appreciated as usual.

Regards,
Nevin