When I raise seed I use a seed raising mix from Bunnings.
Once they get to seedling stage I make my own mix, it's 50/50 Serales premium potting mix and Brunnings Coir. I then add a heap of Perlite to it all to help drainage.
It seems to work okay, the coir comes in a solid block you just add about 27 litres of water to expand it all.
Once you go to this page http://www.foodstandards.gov.au/foodstandards/nutritionpanelcalculator/
Make sure you click on
then click on I Agree then Proceed to the Nutrition Panel Calculator (NPC) then Start a new recipe once this page comes up select add ingredients and search for what you are using.