Important Question about Sunshine#4, enter please

Okay here comes a real stupid question folks. I am using SunShine#4 which is hydro, but it looks just like soil. I am hand watering them. I use Supernatural Gro Terra for vegetative nutes. I have a quick question here. On the nutes it says, "For organic soils: Use up to double strength. Apply every 2-3 weeks depending on rate of growth and fertility of soil." Now, I thought the guys at the store told me to only use this every 7-10 days with the SunShine#4, but I am getting the feeling it should be used every time I water, does anyone know? I used about 1/2 the reccomended dose for small plants, just to be sure. But, should I be using the mixture with the Supernatural in it everytime I water? A quick reply would be great as I think I've been doing this wrong. If I have been doing it wrong (guess it's only been four since I gave em nutes on Monday) are the plants stunted? They look healthy as hell but maybe they are super hungry?