@Luchio I now only use 2 additives in tap water, with perfect results and now days have no issues at all. Ever. The first is Power Si. i add a few drops to each watering and then stop using it about 2 or 3 weeks before harvest. The second is Powerfeed by Seasol. Again, i just add a splash of it to each watering up until the last week or 2 before harvest.
The best advice i ever got with growing was "Its far too easy to kill a plant with kindness"