Bio-Bizz Grow/Bloom

Ok my plants are ready for their first feeding. I'm using a 10 gallon bubble bucket with two plants.

I mixed 3 teaspoons of Bio-Grow with 1 gallon of water as directed by the BioBizz website.

http://www.gchydro.com/detail.asp?product_id=xbiogrow

I need to lower my water level because the roots have dropped down so should I replace a gallon of the water in my bucket with the gallon of nutrient solution I mixed? I don't want to over feed my plants.

If you want to know more about what I'm doing look at my journal