I guess that these are indoor plants.

A bad infestation of fungus gnats can result in large volumes of very tiny larvae in the potting mix that end up feeding on tender plant roots. The adult female flies, after mating, lay eggs in the potting medium.

Fungus gnat populations in indoor plants can be caused by a number of factors.

• chronic overwatering
• peaty, fine-textured potting medium that is slow to drain
• commercial potting mix that is infested at the processing facility
• plants were grown outside before brought into the home

Rather than spend time going into your options, I need you to confirn the fungus gnat diagnosis first. Fungus gnats, by the way, are not in any way related to fruit flies.

I think you're on to something! They do look pretty similar to this: http://buginfo.com/flies/proper-fungus-gnat-identification-and-control-techniques/

They also showed no interest in my banana trap.

In most cases, gnats are more a nuisance of a more serious underlying problem than a threat to plants, but bad infestations can lead to root damage, as already noted. The 'more serious' underlying problem relates to soil choice and watering practices. Gnats are not usually a problem in soils that drain well or plants that are watered appropriately. For example, I water about every 4 days while plants are indoors and never have gnat issues because of the soils I use. When using more water-retentive soils, allowing them to dry down to appropriate moisture levels before subsequent waterings goes a long way toward eliminating the type of environment gnats prefer (moist and rotting plant matter).

There are ways to eliminate most of the excess water that tends to refuse to leave the pot when it's only gravity putting on the pressure. For instance, after watering you can hold the plant over the sink and move it downward, then smartly reverse directions to upward. This uses Newton's First Law of Motion to FORCE water out of the drain hole every time you change direction from downward to upward. Try it - it will make a notable difference. More on how to deal with water-retentive media here.

Also, a wooden dowel (5/16" diameter - from any hardware or big box store) sharpened in a pencil sharpener will serve well as a 'tell'. When stuck deep into the pot (like all the way to the bottom) and removed, it will show you when to water. If it comes out stained dark or moist, withhold water.

Al

I'm starting to think these fancy self-watering pots are not such a great idea. Sure they helped while I was on vacation, but my soil seems way too effective at wicking up all the water and turning out very wet.