Update: the diagnosis from the gang here was thrips. I hit the plants (and the grow room) with a pyrethrum spray yesterday. Today I discovered that dead thrips are much easier to spot than live ones. Hehe! My Azamax should arrive tomorrow; I'll do a follow up treatment with that and then add the D.E. (I refuse to look up the spelling on that one again!) and hopefully things will be under control

--diatomaceous earth! Powder o' Death! I like that you're hitting them with the 1-2 mixed punches... they act on them in different ways, so the hurtin' comes in kind!
Did you scour the room and shit/debris/equipment as well? Remember, they're f'ing Ninjas....
-- give them no place to hide! I'm glad you finally spotted some their rotten little corpses....
warm and ready mate, and you'll win this war!
...DE, ASAP,....