CS>How long do silver rods last @5ppm (how many 8 oz batches) ? Do I reverse rods for longer use ? What is shelf life if kept out of light?

[paulmarble:First paulmarble:Last]

I'm new at LVDC CS making and wondered how I could determine how many  batches 
the silver will make @ 5ppm.  Also, do I need to reverse the rods on the leads 
each time ? Do you flip the rods over at some time to  use the other end ?  
What is shelf life of CS in brown bottle and do I  store it at room temp ?  
Thanks..

Carolyn Marble