Wow, thanks for all the info!
As I said, the light went out on its own last night. The system has always seemed to be working just fine. And yes, I can clearly see where the tank is. When we moved in, the area was brown but now it's become more green the longer we've been here (just over two months now).
Jazz, the system is over a year old but hadn't been used. The completed house was vacant/unsold for nearly a year. The builder sold me the property "as is" but has been great in helping me out and coming over to help me out. They also gave me a "2/10" warranty at closing, but of course flood damage isn't covered.
I think I'm okay, but I will definitely have it checked at once I have a month's income in my bank account. The company did have someone check it just last month, so the alarm trip had to be due to the flooding.
And I just put this stuff in last week as a preventive measure:
