I add spring water once a week and about once a month, I replace the water completely. I avoid using tap water because chlorine is harsh for the bamboo, but if you set a bowl of tap water out for 24 hours, most of the harmful elements will evaporate so you can use it in your lucky bamboo.
This plant grows and grows for me with little intervention, and it gives me a sense of peace. If you're bad at plants, lucky bamboo is a forgiving way to bring some luck and some green into your home. If leaves or stalks yellow or brown, trim them away with sharp scissors.
With the elements of wood (bamboo), earth (the rocks), and water, a lucky bamboo arrangement supports energetic balance and harmony. I like to tie a red string threaded with metal feng shui coins around the stalks to bring in the elements of fire and metal as well, so it represents a balance of all feng shui elements. Placed in your southeast sector, it supports prosperity, and placed in your east sector it strengthens family and relationships.