many thanks for this info. I know what you mean about the insoluble calcium. i have found that mixing with warm water greatly reduces that precipitate, till basically there isn't any. its just extra work, have to mix in a separate rez with warm water, fully dissolve, let cool, then xfer to main rez. i have the manutec one and i have used it for veg before but its not ideal for flower. i could add liquid potash to it i suppose, if i wanted to use it for flower. i did find another powder one called ozi magi or ozi tonic monsta bloom, but its even more dear than the oveepriced maxi bloom on ebay! Also i think that is two part. So i guess i just have to pay more for maxi bloom on ebay if i want to continue using it, or switch to something else. thanks again.