Can you post a picture and tell us where you are located? Is your bonsai being kept indoors or outdoors?
You generally can't trust the instructions that come with commercial bonsai. Watering every day sounds like too much, but it depends on the soil (how organic and moisture holding it is vs inorganic and free draining), the heat and humidity, etc. Water it when it needs it, not on a schedule. Use the chopstick method to know when it needs it: Insert a wooden chopstick into the denser portion of the soil and leave it there. Every day remove it and check for moisture by touching it to the underside of your wrist. If it is damp do not water that day. When the skewer is dry water thoroughly until water is running freely out the drain holes.
RE: "keep water in the tray full of rocks" Yes, but that is a humidity tray. It is not to water your plant or soil, it is to keep humidity in the air around it. So be SURE your planter pot is above the humidity tray, so the water is not touching it. If your pot is sitting in standing water, you are definitely killing your plant.
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