There are a number of different hydroponic and aquaponic systems, so it is difficult to give you specific information for what you are using. Hydroponic systems differ on nutrients based on the type of plant (and fish) produced as well as if there is a substrate used for the plants or not. A number of books and documents are available and a selection of some to start with are listed below.
Your question also mentioned organic fertilizer system. It is unclear if you want a fertilizer regime which is certified organic by the USDA NOP standards? Organic fertilizers for hydroponics is difficult for production for a variety of reasons, so there are none I can list. There are number of companies that provide products that are listed as organic but whether they will work in your system with your crops and if they meet the NOP rules is something I can not answer without more information.
Hobby Hydroponics, 2nd edition by Howard Resh
How to Hydroponics, 4th edition by Keith Roberto
Aquaponic Gardening by Silvia Bernstein
Grow Your Own Vegetables without Soil http://edis.ifas.ufl.edu/pdffiles/VH/VH03000.pdf
Nutrient Solution Formulation for Hydroponic Tomatoes in Florida http://edis.ifas.ufl.edu/cv216
Best of luck in your hydroponic/aquaponic endeavors.