Both excellent fish soil enhancements. However, the Whole Fish is best for all stages of plant growth, especially new plants, growing greens, leafy plants, etc. The Fish Poo has advantages with blooming or fruiting plants. For example, if you’re planting tomatoes, use the Whole Fish while your plant is beginning to grown to develop strong roots and vibrant leaves, but as you begin to get buds and small tomatoes you should switch to Fish Poo to drastically increase the flavor, color and quantity of the harvest.