Actually I think the comment from Turtle was pretty positive. Having an AMK for a closed loop is a good thing, but having it as your main pump is a ticking bomb. About a month ago I decided to buy a pump for a closed loop, an AMK was in my mind, but after reading soo many bad comments about that pump I quit and went with a LG4md, I know it pulls less water but is 100% reliable and that is a determinant factor in my opinion.
I read that almost every AMK pump will leak and/or fail to restart.
Also, to minimize the water flow loss, I connected the outline from the LG to a T and each end has a 3/4" sea swirl. By doing this a minimal loss is achieved and I have a simpler design.
Jason, I don´t want you to take my comment in the wrong way, I really like your tank and your plumbing, but there are some things you might take into consideration when going on vacations and leaving your tank alone with those pumps and don´t come back with a flooded floor.
Great tank, hope everything goes great for you, that spider looks amazing and in general everything is a poem to the eye. Just keep in check the heat from MH´s in those PVC returns.
Congrats.
JMHO
Marco