16 weeks and counting

From seed to hopefully this week, the 16th week, or 9 weeks of veg., and 7 weeks of flowering, it should be close to harvest. I never considered germinating 4 different strains, would consist of possibly 4 different harvest times. I purchase a cheap microscope to look at my trichomes, one major problem, the microscope is to cheap, paid $20 bucks for it, so I can't really tell if they are foggy, amber or clear. I'll have to spend $50-$60 bucks for one tomorrow I guess, that or start my rinsing of my roots tomorrow.
Can anybody tell me how long to rinse the roots before harvest, I read in one grow manual, up to a week of rinsing, a week? Anybody know??
Planting 4 different strains also has created a problem as well. Some are ripening sooner than others I believe, so I think my harvest may take longer than I'd hope. Any suggestions. The attached photo is the one most ripen as of 06-11-10, end of 15 weeks from seed to now

By rinse you mean flush? Which is to give them lots of pure water (3x more water than the container can hold). You do this around a week -> two weeks before expected harvest. It's merits are debatable, but for non-organic grows it's recommended.