Hey Method,
I have used Canna PK13/14 (in fact have almost a full bottle sitting there). I only picked it up because there was no BioNova PK13/14 at the time. I was also suprised to see it said use it for 1 week only, whereas I use to introduce the PK13/14 in incremental amounts each feed. So 1/10th,(flower week 1) then 2/10th (flower week2), then 3/10ths, up until the last and gave it full 1ml per 10litre feed....I guess that it could be done in this way, but I don't think it is an organic nutrient so you probably want to leave it out nearer the end of flowering (30 days I think is suggested - which seems a long time). So yeh, I would say you would be okay to use in incremental amounts, but go easy on it as you don't want to lock nutes out. Do you use the full Canna range, which might also be relevant to when you use the pk13/14?
Morning everyone.
Peace, DST