Walk into any hardware store or pasar raya in Malaysia and you’ll find a whole shelf promising to fix your pest problem for under RM20. Here’s the honest version: hardware store pest control products kill the insects you can see, but almost none of them reach the nest, the eggs, or the colony you can’t see — which is exactly why the problem keeps coming back. They’re not useless. They’re just built for a smaller job than the one most people are buying them for. This is the straight account of what each product does, where it falls short, and the point where DIY stops being worth it.

What’s Actually Inside the Can

Most of the aerosol sprays on that shelf — Ridsect, Baygon, Shieldtox, Fumakilla — run on the same family of chemicals: pyrethroids. Permethrin, cypermethrin, prallethrin, imiprothrin. These are synthetic versions of a natural insecticide found in chrysanthemums, and they kill insects by attacking the nervous system on contact. A direct hit drops a cockroach in seconds.

The interesting part is that professional treatments often use chemicals from the very same family. So it isn’t that the active ingredient is weak. The difference is everything around it: concentration, formulation, and where it’s placed. Retail sprays are made to be repellent and fast — you spray, the pest dies or runs, you feel like you’ve won. A professional product is usually non-repellent and slow, designed so the pest walks through it, carries it back, and takes out the part of the colony you never see.

Cockroach chalk is a different animal — it’s a block of insecticide (often deltamethrin) you draw a line with. Mothballs are naphthalene, which repels but doesn’t kill. Knowing what’s in your hand changes what you should expect from it.

What Hardware Store Products Do Well

Let’s give the shelf its due, because it deserves some. For the right problem, these products are genuinely the correct tool — and far cheaper than calling anyone.

• They kill what you can see, fast. A lone cockroach on the kitchen floor at 2am, a spider in the bathroom, a mosquito buzzing the bedroom — one spray, done.
• They handle a fringe problem. A single ant trail coming through one gap, a few flies after you left the bin too long. Small, visible, contained.
• They’re instant and cheap. No appointment, no waiting, RM8 to RM30. For a one-off, that’s hard to beat.
• Gel bait, specifically, actually works. This is the one DIY product that does reach the nest. More on that below — if you buy one thing off that shelf, make it this.

If your problem is genuinely small, you don’t need us, and we’ll be the first to say so. A can of spray and a bit of patience is the honest answer for a stray pest.

What They Can’t Do

This is where the shelf runs out of road, and it’s worth understanding why rather than just being told.

They don’t reach the harbourage. Cockroaches don’t have a queen and they don’t build a nest the way ants do — they live crammed together in shared hiding spots behind your cabinets, inside wall voids, under the fridge. Your spray hits the few that wander out. The eighty behind the skirting never see it. Worse, a repellent spray scatters them deeper into the walls and, in the case of some ants, triggers the colony to split and start fresh trails. That’s the science behind why cockroaches keep coming back after spraying.

They don’t kill the eggs. A German cockroach egg case carries up to 40 eggs, sealed inside a hard shell the spray can’t penetrate. So you kill the adults on Monday, feel victorious, and the eggs hatch a fortnight later. Same with ants in the kitchen — kill the trail, the queen keeps laying.

The protection doesn’t last. Retail residue gives you a few days, maybe two weeks. Then it breaks down and the gap reopens.

They don’t seal the door. No spray closes the gap a rat is climbing through. For rodents, the whole game is finding and sealing the entry points most people miss — poison alone just keeps the buffet open.

“Hari tu rumah macam kena serang lipas kecik kecik. Stress kejap. Pasang perangkap je penuh. Pasang je penuh.”

— Hanis Zalikha, after the small German cockroaches turned up in her kitchen. When the traps keep filling up, that’s a colony talking, not a stray — and no shelf product clears a colony on its own.

A Product-by-Product Reality Check

Here’s the shelf, item by item, with what it really earns its place doing.

Three of these deserve a verdict in plain words. Gel bait is the smart buy — it works on the same carry-it-home principle the pros use, so for a moderate cockroach or ant problem it’s the best RM20 on the shelf. Place it near cabinet hinges and in the back corners, not out in the open. Cockroach chalk and mothballs are the ones to be careful with — chalk is a real poison dressed up to look like classroom chalk, and naphthalene only repels and carries genuine health concerns. Ultrasonic repellers are the one to skip outright. If a plug-in box that does nothing could clear a house, none of us would have jobs.

A call in Kajang last year — a family had been spraying a kitchen ant trail every other day for two months. Every spray cleared the line for a day, then it came back somewhere new. The colony had split under the floor tiles. We swapped them to a single bait placement and the trail was gone in under two weeks. They’d spent more on cans than the bait cost.

— Job notes, Nomobug field team

When the Hardware Store Is Genuinely Enough

The honest rule. If the problem is small, visible and contained, the shelf is the right answer — and we’ll say so. Spending RM200-plus to fix something an RM20 bait would clear isn’t a deal worth selling.

Most pest companies won’t tell you this. We will. Skip the professional and reach for the shelf if:

• You’ve seen fewer than 5 cockroaches and found no egg cases. An RM20 gel bait near the cabinet hinges clears it in about two weeks.
• You have a single ant trail through one visible gap. Bait the trail, then seal the gap with silicone.
• You’ve got mosquitoes after heavy rain. Empty the pot trays, clear blocked gutters, tip out anything holding water. No chemical needed.
• You caught one rat in a snap trap. One rat is not a colony. Monitor for two weeks before calling anyone.

Knowing when to wait is half of getting pest control right.

When DIY Stops Working — and You Call a Pro

The shelf has a ceiling, and these are the situations that sit above it:

• It keeps coming back within a month. That’s a colony you can’t reach, not bad luck.
• You’re finding egg cases but can’t find the nest. The eggs are protected; you need to treat the harbourage.
• It’s structural — termites. Never a DIY job. A shop spray does nothing to a subterranean colony eating your joists. That’s what proper termite treatment is for.
• It’s hidden — rats in the ceiling void. You can’t bait or seal what you can’t reach.
• It’s spreading across rooms. Once it’s in more than one space, surface products are always one step behind.

The cost question is where DIY quietly loses. A new can every fortnight for six months adds up — and you still have the pests. Here’s the comparison at market rates: