If growing in a small pot, you can use Mr Ganick Cactus & Succulent Food as fertilizer. This product is specially designed for cacti and succulents, providing sufficient nutrients to help aloe vera grow healthier. To use, simply apply 4-5 drops of fertilizer on the soil surface once a week.
If growing in the ground, you can use Mr Ganick 258 Fruit Tree Fertilizer or Mr Ganick 426 Melon & Fruit Fertilizer. Apply a handful of fertilizer evenly around the aloe vera once a week. Remember to water after fertilizing to help the nutrients dissolve, ensuring the plant absorbs them effectively.