It works!

Preliminary testing the overflow system was promising, the primary overflow didn't make a sound once it was submerged and the secondary overflow kicked into action when i simulated a tube blockage by closing the primary overflow outlet valve (which is nice!)


'Sipping' action of the secondary overflow




These photos show the blockage protection for the first overflow, made out of cable ties and eggcrate.


This is the blockage protection for the second standpipe