Gnats don't bite. They don't carry the same disease risks as cockroaches or mice. But anyone who's tried to eat dinner with a cloud of them swarming the kitchen knows they can take a livable apartment and turn it into one you can't wait to leave. Gnats are especially common in multi-family buildings in Waterbury, Hartford, and across central CT — here's why, and what actually works to get rid of them.

What "Gnat" Actually Means

"Gnat" is a catch-all term. In Connecticut homes, the small flies most people call gnats are usually one of these species:

• Fruit flies — light brown, attracted to ripe and fermenting produce
• Fungus gnats — dark gray-black, attracted to moist soil (think houseplants)
• Drain flies — fuzzy, moth-like, attracted to organic sludge inside sink and shower drains
• Phorid flies — fast, jerky flight pattern, attracted to decaying matter and sewer breaks

The species matters because each one breeds in a different place. Killing the adults you see doesn't solve the problem — locating and eliminating the breeding source does.

Why Multi-Family Homes Are Especially Vulnerable

In a single-family home, you control all the variables. In a duplex, triplex, or apartment building, you control your unit — but you share plumbing, walls, and waste lines with neighbors. That changes the math:

• Shared drain lines let drain flies breed in pipes you can't access
• Shared waste rooms and trash chutes attract fruit flies and phorid flies
• Hidden moisture problems — a leak in the unit above can sustain a fungus gnat population in your ceiling
• Sewer line breaks or dry P-traps in vacant units can release waves of phorid flies into occupied units

This is one of the most common reasons gnat problems return after seemingly thorough cleaning: the breeding site isn't in your unit.

What Actually Attracts Them

Gnats follow three things, in this order: moisture, organic matter, and light . The "attracted to light" part is what most people notice first — gnats clustering at windows or lamps — but light is only what concentrates them, not what created them. If you've checked for standing water and rotting produce and still have gnats, the breeding source is likely something less obvious:

• The grunge ring inside a rarely-used drain
• A slow leak under a sink or behind a dishwasher
• Overwatered houseplants — even one
• A garbage disposal that hasn't been deep-cleaned
• A recycling bin with a sticky bottom
• Plumbing or sewer issues outside your unit (shared walls, building risers)

What You Can Do First

1. Inspect drains. Pour boiling water down each drain in your unit, then check 24 hours later for activity at the drain opening.
2. Move or repot houseplants. If gnats appear at the soil line when you water, you have fungus gnats. Let the soil dry between watering and consider repotting with fresh medium.
3. Take out compost, recycling, and trash daily for a week.
4. Use apple cider vinegar traps (vinegar + a drop of dish soap, covered loosely with plastic wrap and small holes) to confirm the species and reduce adult numbers temporarily.

If the problem persists past a week, you're likely dealing with a breeding source you can't access alone.

How ProSource Handles It

For gnats in multi-family buildings, we don't offer a one-time service — and we'll tell you that on the phone. The reason: a single visit can knock back adults, but if the breeding source is in a shared wall or a neighbor's unit, the population rebuilds within days. We start with an inspection to identify the source, then build a treatment plan that addresses both the visible activity and the harborage.

For property owners with multiple units, an ongoing pest control program is the most cost-effective solution. For tenants, see our guide on why landlord approval matters for pest control.

Get an Inspection

Gnat problems rarely fix themselves. The longer the breeding source sits, the harder it is to find and eliminate. For related reading, see Tips for a Pest-Free Kitchen.

Call ProSource Pest Solutions at (203) 405-9856 or request an inspection. We service multi-family buildings throughout the Waterbury / Southington / Hartford service area.