Canna a+b

despite canna's coco infopacket, it doesn't require 'special' nutrients. it's a soilless medium. you can use anything that is good for a soilless medium. If the coco was leaching anything, it's not by this stage of the game or you would have seen issues, so you don't need excess Ca or Mg compared to any other soilless context. those CES are already at equilibrium - equal amounts lost and gained results. So anything that is 100% plant available and 100% soluble that you can mix that results in a similar weighted-average-by-dose ratio of the spectrum of nutes provided will have similar results. they only show npk on the front, but the secondary ones are just as important and will be listed in a percentage on label somewhere. Get the ratios the same, provide at same concentration, and in a soilles context it's pretty much going to have a very similar result gauranteed. much smaller pool of potential ingredients involved. For three days? try watering without runoff (minimal to be certain it is fully saturated) and it'll probably make it with minimal effect. If it's longer just don't use any sort of slow-release option and you can correct any imbalance with some excess runoff when you get your canna a+b restocked. Consider dry nutes. You can mix 100:1 stock concentrations (10mL per L dose) to avoid mixing it up every irrigation and spend about 1/5th the money. Even more if you pay athena or floraflex prices, lol. 1/10th.