PlantGuy's Roll your own Slow Release Substrate Fertilizer 100 tabs (free shipping)

Maybe a stupid question, but I assume you just stuff as many of the little balls as you can into the capsules and close them? Then shove them into the substrate? How far apart should they be and how often do you add more? Thanks!

Yes that's correct.    Just place them every 4 square inches or so and replace every 6 months .