Since building our pool, we have used a dog alarm on their collars, so if they would fall in and we're not out there, a 120dB shrieking siren in the house will allow us to get there very quickly, even if by some chance we were sound asleep (which isn't possible, since we'd have to be awake to let the dogs out). Our dogs are corgis and with those short little legs, they can't climb out anywhere but by the step. If they fall in, a little bit of panic sets in because most corgis hate the water and they don't always swim right to the step.
We have also taken them into the pool 2-3 times a week and reinforced where the steps are by taking them to different places in the pool and gently guiding them to the safe spot to get out. At first we did this with a life vest on (on the dogs, not us), and graduated to doing it without out. Once the water was warm enough for swimming the second year, we reintroduced the process so continue to emphasize to them how to get out.
For several months this path year, our dogs were NEVER outside alone as one of them blew a disk and had emergency surgery and was paralyzed for several weeks. She is recovering well and able to be out and about on her own, although not up to running.
After extensive research when the pool was being built, and prior to knowing anything about this website, we went with the Safety Turtle system. Currently, one of the kid's collar tags has busted and we need a replacement. Since they are not cheap, I thought I'd canvass members to see if they have any recommended products. Have been nothing but happy with Safety Turtle, but can't hurt to check. Backyard is fenced and combination locked, so no other dogs or children can get in. A frog occasionally, but they don't drink much.
I did do a search on the forums and found some previous threads but they were older than a year so no posting on them.