Once you have a Walstad Aquarium setup ready, you may face nutrient deficiency in the soil substrate.
To add some soil/nutrients in the Walstad Aquarium substrate follow this process:
1. Mix some Red Soil and dry organic Manure in the ratio of (4:1). Note: Red Soil contains lots of Iron.
2. Add some water to bring it to dough like texture.
3. Roll half an inch diameter balls from this soil dough.
4. Dry these soil balls in the sun.
5. Now wrap each of these dried balls in newspaper/tissue.
6. These wrapped balls can now be easily pushed into the Soil substrate in the aquarium without tearing down the aquarium.