General usage questions

[boxpin]

I have just installed an Aquamist hfs-1 with a dds-3 gauge. I have some questions.

1. The flow sensor without a jet will peg the gauge, with a jet I get to three bars. Is this correct or adjustable?

2. What do the 'S' and 'B' mean at the two sides of the gauge.

3. I would like to be able to turn the entire system on and off with the gauge button. Is that possible? The button now appears to be only turning the gauge on and off, the hfs-1 continues to function(because of the ignition wire)

Thanks,

boxpin