hmm, seems to me you should start worrying about harvesting, not feeding some more. If you have been flushing for a week then give it another week or maybe 1/2 week and harvest! 53 days is plenty enough. Keep in mind also that you are looking (with a magnafying glass) at the individual trichomes (crystals) on the leaves and hairs to start changing colors, not the hairs themselves. The hairs may indeed start to change colors at some point in time depending on the strain, but your main focus should be the trichomes.

You have nice fatty fist sized buds there. Time to get your smoke on