Rapid die off at day 35... desperate for help

[SaBeS]

Looks like salt build up to me. I second flushing the media with a few plants and see if that helps.

 

[TanzanianMagic]

There's your problem mate.

CannaFlush can be used throughout the entire grow. Not plugging, but if you're using their coco to begin with, might as well stick with the rest of the tested line.

The way I see it, you only need to the high PK until the flowers are bulked up. After that, a Silica source (preferrably without P or K, like SiO4) and some minerals (seaweed) is all that is needed to feed the trichomes, which are nearly complete made of Silica.