Hello mikkel753951,
Like I mentioned I don't have any experience with making my own
nutrients, so I honestly cant tell you. But I believe you can leave a comment for Daniel on the blog. But if you explain your question and give them the recipe you plan to use (I assume it's the one from University of Arizona), and e-mail it to them directly, I think they would be able to answer that for you. Here are some links to their Agriculture and Life Sciences departments.
College of Agriculture and Life Sciences (homepage)
College of Agriculture and Life Sciences (departments)
College of Agriculture and Life Sciences (deans office, e-mail address at the bottom of the page) I'm sure he can at least forward your question to the right person.
College of Agriculture and Life Sciences (contact information) There is another e-mail address as well as phone and fax numbers.
College of Agriculture and Life Sciences (Locations and Contacts for Agricultural Research Centers)
student information for the College of Agriculture and Life Sciences (another promising e-mail phone and fax)
Anyhow I'm sorry all I can give you is links to sources of information rather than an answer. But I'm sure if you copy and paste the same question to all the e-mail addresses, even possibly fax or phone (long distance charges permitting), I'm sure someone will be able to answer the question for you, and/or at least forward it to the right person. Especially considering the recipe was developed by them (assuming that's what you plan to use).