Final Flush Last Week!

I'm hearing about flushing them with ice water and feeding them ph'ed ice water for a week to add color i'm looking at different ways of going at this and I have also heard of cutting them 2 hours before the light cycle after the week flush please respond with your expierience and tips and i will give u bud porn after hahaha... Thanks *looking for last flush advice for better buds.*

 

I'm wondering if that's only with hydro system's since it's setup to use no growing medium and has direct contact with the water and constantly circulates at 55 and not just being 55 and slowly changing the temp back up. but i will fill everyone in