Yes, you should soak your coco coir before planting. Since it has great water-absorbing capabilities, pre-soaking it will allow the coir to expand and absorb water. This process also helps remove excess salts that might be present. You should soak coco coir at least 15-30 minutes before planting. However, it’s often recommended to let it soak for up to 24 hours for optimal hydration. Then gently squeeze out excess water before using it in your hydroponic system.