Nutrient concentrations questions

I have a bloom nutrient called Plagron Terra Bloom, which has NPK 2 2 4. I received an additive with it ,concentration 0-13-14 NPK. It is labeled as being organic and can be used with every watering.
Here are some links
http://www.plagron.com/nl-nl/product/1/46/24/terra-bloom.aspx
http://www.plagron.com/nl-nl/product/1/46/32/pk-1314.aspx


Almost all the nutrient brands have some different NPK concentrations, I'm not sure why, nor what concentration makes a nutrient "better" , or "safer".....Can anyone clear this out for me?

I predict a google search in your future. There are several articles in laymans terms that explain this. And i wish plagron was available in the u.s.a. Ive heard good things about the line from European buddies. Get to researching and reading.