Small brown bugs under leaves, no not mites...

So I am defoliating my plants right now, gonna harvest tonight/tomorrow and I have found a few leaves that seem to have clusters of these brown bugs that kind of look like root aphids and are about 3-4 times larger then mites and seem to have smaller exoskeletons by them. They haven't seemed to effect the plants at all and the one plant I am finding them on has the least amount of mites.
Have I discovered some sort of mite predator?!

Nobody has ever seen any other bugs besides mites or fungus knats on their plants?!

could be aphids

Thought of that, but I havent really seen brown ones before, they werent causing any leaf damage and they didnt have the dual exhaust pipes on their abdomen

There are over 4,000 species of aphids, many of them brown and not all with the "dual exhaust pipes" (they're called cornicles, on some species like most root aphids they're more visible than others). That's where the sticky shit they leave on your plants comes from, just in case it ever comes up in Trivial Pursuit. Different species cause different degrees of damage. One of the more common brown colored aphids is the corn aphid, which won't hurt your plants too bad unless they just get seriously out of control. They don't feed on the leaves and tend to cluster at the joints of stems. In any event, a thorough cleaning and bleach job on any equipment to be reused would be recommended, and some diatomaceous earth scattered on top of your soil (if you're in soil) on your next grow might be a good idea. Good luck.

Thanks for the info, I only saw them on one plant and haven't seen them since, Im thinking Im getting these random pests from the gaps I have in a small window where my 12" ducting goes out. I'll keep an eye out for them in the future.