Any chance you have whitefly?

For aphids, removing the affected leaves is a good idea. Our local university recommends an aluminum foil much for soil based plants although I donÂt know how that would work with your system. Some growers companion plant  fenugreek & chives. Also, ants herd aphids although it does not sound like you also have ants.

Here are a couple of aphid threads on GW:

http://search.gardenweb.com/search/nph-ind.cgi?term=aphids&forum=pests&forum_name=Garden+Clinic

http://search.gardenweb.com/search/nph-ind.cgi?term=aphids&forum=pepper&forum_name=Hot+Pepper

I think it's whitefly. There are these tiny whitish insects that would infest leaves in large groups. Sometimes it gets so bad, I just cut the entire leaf off and dispose of it. If it's not too bad, I scrape them off. If you look into the water, you can see dozens of these things floating around. I can't figure out where they're coming from. There's also these larger brownish insects, but fewer of them. Since it's hydroponics, ants have no access to the plants so aphids are pretty much out of the question. Should I just take the whole plant and dip it in water to get these things off?

I had one infestation in hydro g'house.

I threw out all the plants, I cleaned the room thoroughly, I cleaned hydro stuff thoroughly and I let the room sit for a month or two.

Haven't had any more trouble in 10 yrs.

I keep dirt out of the g'hse and I keep dead plant material cleaned pretty well from all surfaces.

I had both a whitefly & aphid infestation after some neighbors who did not take care of their plants moved nearby. I also do not like insecticides. On my outdoor plants I kept cleaning underneath the leaves by flushing them with water or wiping them with an alcohol pad. I removed any leaf that looked like it was developing a population. It did not solve the problem but minimized it.
I also had a problem inside my greenhouse. Like Willard, I got rid of all the plants & media, scrubbed the greenhouse, did not use it for awhile, & started from scratch. My neighbors & their infested plants eventually moved, & thatÂs when the pests finally stopped.

You need to make sure what bugs you have if you want to specifically treat your problem. UC Davis has a good site for pests & peppers. You can get a magnifying glass & compare your bugs to the pictures. Sticky traps may help. If you are going to keep the plant you need to isolate it from other plants or they may become infested. Also, here is also the USDA whitefly database:

http://whiteflies.ifas.ufl.edu/wfly0002.htm?

This is a pretty good gentle all-around pest control solution:
1 part Murphy's Oil Soap
1 part alcohol
9 parts water

Spary every 3 days to get rid of all stages of the life cycle. For the white flies try vacuuming or yellow sticky traps.

I use a ladies compact mirror to look under the leaves for white fly. Much easier than bending the leaves up or bending you back. Even if you only see one white fly get that sucker, cause one will soon become many.