
This appears to be a Drain Fly or Bathroom Fly in the genus Clogmia in the Moth Fly family Psychodinae. We typically get identification requests regarding Drain Flies from homemakers who are perplexed by their appearance in bathrooms and kitchens. In the home, the larvae live in the sludge that collects in drains and pipes. According to BugGuide: “Larvae feed on algae, fungi and bacteria in sewage and organic sludge; adults feed in polluted water and on flower nectar.” We don’t believe they have any interest in your plants, but rather in the hydroponic system itself which may need some cleaning and maintenance. We are not convinced the webs you mentioned are related to the Drain Flies. BugGuide also notes: “In the home, females lay irregular masses of 30-200 eggs in the organic gelatinous film lining drains, particularly in bathtubs and showers; eggs hatch 32-48 hours after being laid, when ambient temperatures are 70ºF (about 20ºC), and larvae pupate 9-15 days later; pupa stage lasts 20-40 hours; development time from egg to adult is 7-28 days, depending on temperature and food availability; adults live for about two weeks” and “Larvae play an important role in purifying sewage in industrial sewage treatment plants. Adults are very weak fliers, covering only a few feet at a time in short erratic flights.”
http://www.whatsthatbug.com/category/flies/bathroom-flies/The Bathroom Fly is a common household pest that belongs to the family of Moth Flies, hence your confusion as to its identity. Indoors Bathroom Flies breed in the sludge that accumulates in drains, and that is where the larvae can be found. Exterminating the adults will not help with your problem. You need to get to the larvae. Pouring chlorine bleach down the drains once a week may help.
The Bathroom Flies, though a nuisance, are basically harmless.
http://www.whatsthatbug.com/2012/03/25/bathroom-flies-infest-home/I've gotten quite good at hitting them with a whip like movement of a towel. Some of the bodies seemed to have red eyes. They're kind of cute but them again ick where they came from and that they like nostrils when you're trying to sleep if their population is high and there's not enough room in the drains? ADDS Bleach to the shopping list.