Q.What Is The Water Level Needed To Grow Snake Plant Fully In Water?
I have a snake plant grown fully in water. Some people advise me to leave the water level low… while others advise me to keep water level higher. So which is right? I have a pot of snake plant in a small glass filled with small pebbles and water. The roots rotted. I am now leaving the plant without pebbles in a different glass jar without pebbles.

Certified GKH Gardening Expert
You don't need pebbles to root anything. They may have had bacteria that caused the roots to rot. The water doesn't need to be very high, about one-fourth as high as the cutting, which only needs to be 4 or 5 inches. Don't forget to change the water every few days to prevent the buildup of bacteria. This article will help:
https://www.gardeningknowhow.com/houseplants/snake-plant/snake-plant-propagation.htm