Before I got any fish, I took a cup of my water to the fish store and they said it was ok for guppies. I can find out the GH as I didn't ask about it at the time.
The tank has been set up for 5 months.
I don't think I cycled it, I added bacteria from the fish store and a water treatment for a week before I added any of my guppies.
I don't know the specific levels of anything, but I took the water to the fish store after the week long set up and they tested it, said it was good to go.
The guppies were not ill, but when I got them, they were all different sizes. I didn't think it would be an issue at the time. Unfortunately, the smallest one (Gideon) got attacked by the biggest one (Bubba jr.); after more research I think he was bullied, but at the time I thought they were just chasing each other for fun. Then, my little teenaged sister saw Bubba jr attacking Marco so she took Bubba out of the tank, panicked, and flushed him...!