Sorry to hear of your loss.
When I do water changes on my saltwater tank, I use a tap water filter to fill a 5 gallon bucket. After forgeting that the water is flowing and a few wet floors later, I now use a kitchen timer to remind me when the bucket is almost full.
Ive been doing the same thing with my saltwater tanks, except i use RO water. I have 2 or 3 float vlaves laying around that should have been installed in my sump, but apparently i never made time to install one.