Fill the fishbowl halfway with glass marbles.
Insert each bamboo stalk, firmly, into the marbles, with the roots pointing downward. If necessary, remove some of the marbles to achieve this task, and put them back in the bowl once the bamboo stalks have been anchored.
Fill the bowl, slowly, with fresh, clean water. Be careful not to jostle the bamboo stalks. Hold the stalks in place with one hand to assure they don't get knocked loose by the water.
Introduce the bubble-eye goldfish to the bowl of water. Bubble-eye goldfish are decorative and interesting to look at. They also thrive well in fishbowl bamboo topiaries.