The Soil Builder product adds complex carbon acids to the soil, and also contains a faint dose of N-P-K. It is buffered, and hence mixing a small dose of it with another buffered fertilizer such as Banana Fuel should not cause any precipitates. Worm Farmer, a cap-full of Soil Builder every few months for your potted plant(s) seems appropriate. A little bit does go a very long way.
For people with a lot of potted plants or a larger property, the quarts and gallons of 12% Humic Acid concentrate are more cost effective. Here are the application guidelines:
For 2-3 times per year maintenance applications on garden or crop soils, set sprayer to 1/4 teaspoon per gallon and wet soil to approximately 1/4 inch depth. For carbon-deficient soils, apply a maximum of 1/2 Tablespoon per 100 square feet or 3 quarts per acre as a soil drench diluted at least 1:50 with water and usually 1:128 to acheive the desired coverage of approximately 1/4 inch saturation depth. For example, a hand-pump sprayer with 1/2 gallon of water and 1/2 Tablespoon of Grow More 12% Humic Acid is sufficient for a 10' by 10' (100 square foot) area of carbon-deficient soil. Afterwards, a twice- or thrice-yearly maintenance application applied for 2 to 3 years will correct native deficiencies in most soils.