Livewell Controls Confusing me.

[ACRon]

I have a 2003 520 DVX. The livewill switches in the push button panel are as follows (see attached picture) Aerator Pumps 1 and 2. Aerator Timer H, M, and L. The manual switch is Recirc, empty, auto. This is new to me and has we confused as to the exact functions.

If I understand:
Recirc just recycles live well water and outside water is blocked.
Auto recycles and fills from outside water except when on plane.
Aerator Timer is simple H=most frequent aeration and L=least often aeration.
Aerator Pumps 1 & 2 is confusing. Is it just a backup system? Are there two pumps?
Empty lets it drain out through the fill transom intake?

Where does overflow drain the water to?
Is there a pump out?


Thanks,
Ron