There is an article called "A Strong Hypothesis" on Science Buddies that might be helpful. It gives you the format of a hypothesis, tips on how to write a strong hypothesis, and examples of good and poor hypotheses. The link to the article is https://www.sciencebuddies.org/blog/a-strong-hypothesis
In order to find research, I recommend that starting with "When Science is Sweet: Growing Rock Candy Crystals"(https://www.sciencebuddies.org/science- ... background
) from Science Buddies. Although it is about a slightly different project, the overall concept of it is similar to your experiment. If you click on the "Background" tab, you will find background information that you need to complete the experiment successfully. There are terms found there that apply to your experiment. They could be researched further to gain a deeper understanding.
In "When Science is Sweet: Growing Rock Candy Crystals", it suggests to observe rock candy growing jars once a day for a week. However, I think that this depends on how much time you have until the project is due.
I hope this helps. If you have any questions, please let me know.