This VDO clip talks about Hydroponics systems that is the another way to grow lettuce without soil but use water provided it contains the proper nutrients and fertilizers.
First, the seeds are coated by clay that holds in moisture to nourish the seed and it are planted in the foam block with holes called an oasis. Then, workers set them afloat the pool of water. The technicians always check levels of oxygen and fertilizer that's the key to hydroponic growing. In winter the seedlings will grow slower than the summer due to less light. When the plant is grown up, they separate the seedlings apart. After that, move the seedlings that have strong roots into other zones. After this process it will be floated on the water again. This hydroponic system relatively safe. It produces plants without the use of pesticides and fungicides for growing because it's all indoors fertilizer can contaminate the environment.
Form this VDO clip I have learnt about how to made Hydroponic lettuce by Hydroponics systems. I think it’s a great way because it reduces the use of chemicals and healthy. However, it has relatively high production cost and need more attention. Probably not worth making