Growth on stem! Maybe nute blood? 3rd week of flower, something weird on some stems

Hello,
I'm in my 3rd week of flower with an aero system, the plants are awesome looking, but tonight I noticed a couple of whiteish dots on a leaf stem, it was blocking a bud anyway so I snipped it to have a closer look. There weren't spots, they were like hard little balls, kind of creamish in color, stuck to the stem of the this leaf. With a magnifier they kind of looked like they were once a bubble, of maybe a thicker liquid, that popped, because these little balls have a hole. At first I thought, oh crap, fn spiders or some shit, but I took one off and kind of smooshed it between my fingers and it turned to a damp powder, which makes me think it's some sort of 'outgassing', for lack of a better term. I searched the forum for 'balls on stem', but found nothing. Have you ever seen this?
I use Humboldt Grow, Micro, Bloom, Sea Mag and Prozyme + Hygrozyme. PPM has been about 1400 for the last week, now down to 1300, Friday is flush day, I flush weekly. Ph is around 5.6 to 5.9. 13 gallon Res temp 67-70, room temp 68-72. 2x 600watt lights. 15 site aero system using 8 sites.
Thanks!

cannabis herpies!

Help guys, any ideas what that stuff is?

That's new to me, I have never seen anything like that. Good luck on finding out what it is. I am sub'd just out of curiosity.

im thinking some kind of bug have you cut one off the stem yet? are they liquid, if so thats an infection of some sort, you need to isolate and water with TAP water, it sterile and will drive out whatever is causing this.

looks like a bug of some sort

Thanks for your replies. This stuff is the same color all the way through, which makes me want to think it isn't bug related. I look at my plants real close, especially now, and I have never seen a bug of any sort, yet.
This 'stuff' is very infrequent, I mean you have to really look to find one and they are only on leaf stems, I haven't found any on leaves or the stems.
Hey polyarcturus, do you mean flush with just plain water? I did flush my res this last Friday, was around 1250ppm. The plants are doing so well I hate to cut the nutes, but the alternative may be worse. So, flush and run with plain water?
Thanks!

whoah wait i assumed it was in soil. did you cut one off yet? was it a liquid?solid? dont jump to any conclusions yet. put some new pics up? what kind of sytem are you running?

ah ok aero not dont cut the nutes just grow it out and pay attention to it i thinks it an infection or virus of some sort, might never hurt the plant might kill it but in aero there isn't much you can do it its affecting one plant