WHICH TANK FILLS FIRST? ft. Simone Giertz

The riddle at 5:41.  Assuming yada yada about gravity and flow rate / flow restrictions, and all containers are open / no "vacuum pressures."
A spills over to B.  B spills over to C.  C would spill over to D, but is blocked, so spills over to J.  J "tries" to spill over into I, but ultimately spills into L before getting any fluid into I.  L would spill to H, but is also blocked, so instead spills to F.  F and L fill now, but the top of F is lower than the top of L, so F fills first.  
If the blockage from C to D is removed, then G would fill first.  The fact that the outlet from D is below the top of G doesn't matter, since all containers are open at the top.  
If the blockage from L to H is removed, then H fills before F, so H fills first.