Lead Pump Alternation

[Dino]

I have a panel with 6pumps. Will it be a tricky to do a circuit to run all the pumps depending on the level of a tank, so as the level drops a pump will run if the level continues to drop another pump will come on, this part i think i can do but the customer wants to rotate the lead pump daily and this is the bit i can't get my head around.

[ndzied1]

Here is an application for 2 pumps.  Perhaps you could start there and extend it to your 6...

http://trainingscenter.moeller.net/applications/pumps-valves-compressors/immersion-pumps.html