One airstone is more than sufficient for a single waterfarm too btw. You only have to use a 1/4 tsp of gh micro, gh grow, and gh bloom also if you do feed the seedling nutes. But I usually feed the plants nutes when their 3rd set of leaves start coming in. Sometimes I just wait till I see yellowing starting on the lower leaves showing that they are sapping energy out of the lower leaves to feed. Hope that helps.:hippy: