I'v done a bit of reading and from what I can find, canna pk13/14 is only needed for 1 week because you already have the required dosage of it in canna a+b (I think that's what the canna bloom is called). Where as the hesi bloom nutes don't have it in, so you need to supplement your plants with pk13/14 for a little longer.
From what I can gather which ever brand of nutes you use, your plants get about the same amount of pk as its in the bloom nutes.
Someone please correct me if I'm wrong :Gold: