I do pest control in Southwest FL. For indoors, sweet ant bait is the "preferred method". Talstar for outdoor use (not granules, the white serum pre-mixed solution or in powder form). With a gallon sprayer you then use the the solution. Two ounces per gal is what I use, (three for flea jobs coupled with a birth control chemical). I often spray the baseboard inside as well. You'll often read that spraying indoors will only make the problem worse. This "can" be true but there are a lot of x-factors.
If I go to a house and can actually find an ant (like going to the doctor, the pain stops when you're there, ironically), I squeeze out some bait in front of their path. They will call their friends, very fast by releasing their "come and get it" pheromone. I'll let that sit 5 to 10 minutes. Several things are then judgment calls and differ from person to person. If I get a good showing (for a house, a couple hundred or more), I only bait. After the ants leave the bait, they will head back to the colony, most of the time. Track them. If they stop or start going in circles, blow on them to motivate them. You'll see them butt heads with ants along the way (giving them a taste). You will rarely track them back to their nest since it's most likely in the walls. You will see them typically head up behind the microwave, or an electrical outlet. When I lose them to a void, hole, crack or crevice, I'll then normally gas it with a non-residual insecticide made from chrysanthemums. This is a contact kill gas and leaves no residue, but be sure to ask and make sure that no one around is allergic to flowers before use (seriously). The talstar and bait are non-allergenic. More than likely you'll find them coming in around cracks around the windows and doors. People here in Naples leave their doors and windows wide open all the time. That's fine as long as you are doing a good routine of maintenance (spraying). Home owners should caulk all these cracks that are caulkable. Behind microwaves is a different story and if you live in a condo, chances are, there's a big hole back there where your vent goes up and out. In those cases you can bait and spray or one or the other.
Frustrations of a bug man:
People will always wipe up what you put down and then call you a couple days later. Condo communities need education and need to be informed about where their maintenance fee is going. Your building exterior should be treated once a month, not every other. Landscapers need to keep trees and bushes away from the buildings. If it touches, go out there at night and watch the thick trail of ants bypassing our chemical around the base of your house and filling your walls. People need to get a hobby and stop sitting outside with their idiotic jet sprayer 5000. The chemical is safe, folks. We've come a long way from arsenic and strychnine. It's not safe for fish (more on that in a sec). Condo associates are not pest control technicians and are often run by a board of volunteers who are just happy to have something to do. I understand and can relate, but take your jobs seriously. I've talked with several presidents of these communities and a couple have told me flat out that it's cheaper to just service people infested time and time again, than to afford landscapers keeping the ever growing tropical branches back from the buildings.
Finally, if your sprinklers are showering your home, you need to tell someone to adjust them. They shouldn't be and that alone will stimulate ant growth, as well as clean off the building’s protective coating from us pest people.
The primary ingredient is bifenthrin in most pesticides. The amount used in your house will not harm your pets. Don't, of course, spray their food bowls, but relax. The amount of actual chemical residual (once the spray dries) in your house is about 1/3 of a teaspoon in total, and that's if you have a fairly large house (not a condo). Bifenthrin is toxic to aquatic animals, so if you have fish, stay a good 10' away with where you spray. Yes, it goes on wet and dries to a microscopic sticky residue, but for fish (since they can't process it) just a small amount kicked up and into their filter can make them ill or even kill them. Don't spray bird cages. Around them? Fine, but not inside them. Again, it won't kill them, but remember your pets can't tell you when they’re in pain. A cat or dog walking through a puddle of it? Fine. It will lick its feet and clean them. A bird? It won't kill them, but I can only imagine how much their feet will burn since they can't immediately clean it off.
Finally, be diligent. If you've had an infection, you've most likely heard your doctor tell you to keep taking your medication even after you feel better. Same goes with ants. If you think you don't have any anymore, try to entice them. Leave some sweets out. A half eaten jelly donut, some chocolate (keep it out of reach of dogs of course), anything. "If you leave it, they will come". If they don't, congrats. Stop baiting what you can't see and keep up a good once a month spray on the exterior. Keep in mind that exterior treatment is essential. Don't believe chemicals (other than granules for fire ants) that say good for 90 days. It’s true if they are untouched on the inside, but not outside. If you wait, until you have them in your house, then chances are high you have an infestation that you might never fully control on your own.
It's called pest "Control" for a reason. They can't be eliminated. A true fact. Total the weight of human beings on earth. The weight in ants is more. Much more.
Oh, one last thing. Help us help you for those who have pest control service already. I can relate to people who don't want to "bug" us. I am like that and don't want to be a "pest" to anyone. People call us with no problem, the first time, and even the second time. After that, they see a few here and there and live with it. Don't. If you have a large infestation, the quicker we take it out, the better. If enough of them die, the colony collapses, but if you leave a few here and there, there will soon be a bigger problem then you started with. Spraying indoors is ok, if you are me, or 100 percent consistent. Imagine being in a platoon being bombarded with something that's killing you all off. What do you do? You split up in groups. Same with ants.
Persistence is the main key. After a treatment, you shouldn't see any more ants after two days. There is no such thing as an ant repellant for ghost ants, so they must walk through the residual in order to die. This will take a couple days, or even 24 hours. After that, if you see one, look for another. If you see two or more? Watch them for a couple minutes. If they're walking out in the open across your kitchen floor, chances are they're about to be dead so there may have been some late comers. It happens. If they are walking in groups again, and sticking to edges, that is a reason to call us back.
Last but not least, when you call us, entice them before we come. I can't stay on any one call for too long and often I won't find anything and you'll be telling me, "But this morning there were hundreds, I swear!" I believe you, but entice them so there's a trail formed or forming when I show up. It only helps you. Resist killing them.
Also, don't think we're in there spraying sugar water. Most chemicals will last 90 days indoors, but you have to keep in mind that the compound doesn't stay there after hundreds of ants pick it up and move on. You only see an insanely small amount of the ants you have if you're seeing them on a normal basis. 90 percent of the colony doesn't leave their nest and there are no chemicals out there that they take back to the nest. Baits they do, but not in a way that infects the nest like chemicals made for other species of ant does (like the white footed ant and good ole Termidor).
If you see a guy wearing clothes that looks like janitor attire, and carrying a can with a hose here in Naples, ask if it's Dan and check me on the spot. I will be using the chemicals I wrote about with a tube of bait in my pocket. Not looking for business (too much already). Only hoping you'll help us that do the job as well as those who want to know what they're up against.
Hey, we deal with bugs here in the tropics, but at least we don't shovel anymore. --Dan