Herbie Overflow - Starting over

[Coralgurl]

I need to redo my overflows - we did our herbie set up incorrectly and finally after 2 years of waterfalls, need to fix this up. I have 2 corner overflows with one drain each. On my emergency drain, we have the pipe slightly higher than the water line by like 1/8". I've read it should be slightly lower to assist restarting the siphon. In this overflow I have a little non intentional refugium going as the water really doesn't move unless my main drain fills - usually due to filter socks. Of course its lower than the top of the tank so no risk of flooding. Should I adjust the height of this drain?

I currently do not have a pipe in the main drain (reason for endless waterfalls no matter how I adjust, it resets to the same level), and I know this should be 6" lower than the emergency - no concerns there. I do have a gate valve on this drain.

And finally, plumbing - I have never secured my plumbing under the tank and I need to do this as well. I have what I need, just have to complete. Is it best to have the pumps on or off to secure? I assume off to reduce the water weight in the lines and then let the strapping carry the weight.

Thanks