I wouldn't clean it with sandalwood.
When you cut lucky bamboo, you need to seal it with wax, if you don't it can get moisture in the bamboo and cause rot.
Lucky bamboo needs fertilizer about once a month. Green Green is great and is cheap and will keep your plant green http://amzn.com/B004490QYI
Lucky bamboo is sensitive to tap water (chlorine and fluoride). You should boil tap water at least, and possibly use distilled water. Chemicals will make your plant turn yellow and die.
Lucky bamboo is not an aquatic plant, and should be transferred into a soil pot.
Since you have a yellowing stalk, you should separate it from your other stalks to ensure no bacteria spreads.
Be careful when changing water, as really cold water, or hot water can cause distress. You really should only change the water about once a month.
Also, to much, or to little light can cause distress (yellowing) in the plant.
My suggestions:
move it to its own container (isolation)
only use distilled water
fertilize it asap with green green
stop using sandelwood
seal the top if its open with candle wax
think about the light its getting