if ur feeding chem ferts like cha ching and stuff i would def flush for a week. that plants looks done but imho i think it will be even better a week from now. i personally like to wait for all the hairs to turn orange i dont like seeing any white hairs. i wait til the hairs recede back into the bud and it is at least 50 percent golden trichs. but a lot of when to harvest is personal preference but i think most people prefer it with more golden trichs. if u grow organically with all types of manures and such in the ground i think flushing is pointless cuz there is no way to flush all the shit out of the ground. but when feeding with chems i would flush, but i also would never feed with chems so i dont ever worry about flushing. but ya like i said i still think that plant has 5-7 days anyways. its ripe but its barely ripe, and the window is about 7-10 days from once its ripe to when it starts to degrade. straight water for a week and pull and u should have some dank bud. but remember when to pull is only half the battle, drying and curing are just as important as to how your final product turns out. just remember for drying: cool, dark, and dry. keep the air moving with a fan blowin but not directly at the plants. keep the lights off, once a plant is pulled the light does the exact opposite of what it did while it was growing, it degrades the thc. and try to keep the humidity down so mold wont be a problem.