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The short answer: Both RMR-86 and Concrobium are effective mold killers, but they work differently. RMR-86 is a fast-acting bleach-based spray that removes mold stains instantly, while Concrobium is a non-toxic, odorless solution that kills mold and prevents regrowth without harsh chemicals. Choose RMR-86 for tough stains and quick results, or Concrobium for safe, everyday use and prevention.
RMR-86 and Concrobium are two of the most popular mold removers on the market, but they take different approaches. RMR-86 is a professional-grade cleaner that uses sodium hypochlorite (bleach) to kill mold on contact. It’s designed for areas where mold is visible and you want it gone fast. On the other hand, Concrobium is a water-based solution that uses a patented polymer technology to encapsulate and kill mold spores. It’s odorless, non-toxic, and safe for use around kids and pets.
When choosing between the two, think about your specific needs. Are you dealing with a small patch of mold on a wall? Or do you want a general-purpose cleaner for ongoing prevention? Understanding these differences will help you decide.
Both products kill mold effectively, but their mechanisms differ. RMR-86 works by oxidizing mold spores, breaking them down instantly. It’s particularly good at removing black mold stains from surfaces like wood, drywall, and grout. You’ll see results immediately.
Concrobium, however, works by creating an alkaline environment that kills mold and prevents future growth. It penetrates porous surfaces and leaves a residue that inhibits mold from returning. While it may take longer to see visible results (sometimes 24 hours), it’s just as effective at killing mold at the root.
If you’re dealing with a severe mold infestation, RMR-86 might be your go-to due to its fast action. For routine maintenance and prevention, Concrobium is a reliable choice.
Safety is a major factor when choosing a mold killer, especially in homes with children or pets. RMR-86 contains bleach, which can be harsh on the skin and lungs. You need to wear gloves, goggles, and a mask when applying it. Also, bleach can damage certain surfaces, so it’s not suitable for all materials.
Concrobium, on the other hand, is non-toxic and has no strong fumes. It’s safe to use around people and animals, and it’s even been approved by the EPA for use in food processing areas. This makes it a better choice for nurseries, kitchens, and other sensitive spaces. If you have allergies or chemical sensitivities, Concrobium is likely the safer option.
Applying mold removers can be messy and time-consuming, so ease of use matters. RMR-86 comes in a spray bottle, and you simply spray it on the mold, let it sit for 10-15 minutes, and then rinse or wipe. It’s straightforward, but you need to be careful not to over-apply because the bleach can cause discoloration on some surfaces.
Concrobium also comes in a spray bottle. You spray it on the mold, let it dry, and then optionally wipe away the residue. It doesn’t require rinsing, which saves time. However, it may require multiple applications for heavy mold growth. Both are easy to use, but Concrobium’s lack of rinsing and harsh fumes makes it more convenient for indoor use.
Price is always a consideration. RMR-86 is generally positioned at a premium price point, but a little goes a long way because it’s concentrated. A 1-gallon jug can cover a large area. Concrobium is also cost-effective, and since it’s non-toxic, you might use it more liberally without worrying about exposing your family to chemicals.
When comparing value, think about the long-term benefits. Concrobium’s anti-microbial residue can prevent mold from coming back, potentially saving you money on future treatments. RMR-86, while powerful, might require more frequent applications if mold persists. Consider your budget and how often you need to treat mold.
Based on your situation, here’s a simple guide:
If you’re still unsure, check out our comprehensive guide on the best mold removers for more detailed comparisons and recommendations.
Deciding between RMR-86 and Concrobium often comes down to the specific conditions of your mold problem. Start by identifying the surface. Is it non-porous, like ceramic tile, glass, or metal? RMR-86 excels here because its bleach base can wipe out stains without soaking in. If the surface is porous, such as drywall, ceiling tiles, or fabric, Concrobium is the safer bet because it won’t cause the same discoloration or material degradation that bleach can.
Next, consider the size of the affected area. For a small patch, either product works, but for extensive mold growth, you may need a combination approach. Some homeowners use RMR-86 first to kill and remove the bulk of the mold, then follow with Concrobium to prevent regrowth. This two-step method can be effective, but always test a small area first and ensure proper ventilation.
Also think about the location. In a bathroom or basement, where moisture is persistent, Concrobium’s residual protection helps keep mold from returning. In a garage or shed, where you might not care about odors as much, RMR-86’s fast action is convenient. For kitchens and food prep areas, Concrobium’s EPA approval for food processing makes it the clear choice.
Finally, evaluate your comfort level with chemicals. If you prefer to avoid bleach altogether, Concrobium is your only option between the two. If you need the strongest possible stain removal and are willing to take safety precautions, RMR-86 is the more powerful tool.
Even the best mold killer can fail if you make these common errors. First, don’t skip surface preparation. Mold often grows on dirt or soap scum, which can prevent the cleaner from reaching the spores. Clean the area with a mild detergent and water, then let it dry before applying your chosen product.
Second, avoid mixing chemicals. Never combine RMR-86 with ammonia or other cleaners, as bleach can react to produce toxic gases. Always use one product at a time and rinse thoroughly between applications if you switch.
Third, don’t underestimate dwell time. RMR-86 needs 10-15 minutes to work; wiping it off immediately will reduce its effectiveness. Concrobium needs to dry completely to leave its protective residue, so don’t wipe it away too soon.
Fourth, ignore the “set it and forget it” mindset. Mold requires moisture to grow. If you don’t fix the underlying water source, such as a leak or high humidity, mold will return regardless of which product you use. Use a dehumidifier or improve ventilation to keep areas dry.
Fifth, wear protective gear even with Concrobium. While it’s non-toxic, it can still irritate eyes or skin in some individuals. Gloves and eye protection are wise.
Finally, don’t use bleach-based products on colored fabrics or unsealed wood. RMR-86 can cause irreversible damage. When in doubt, test a hidden spot first.
While RMR-86 and Concrobium are top contenders, other options exist. For a natural approach, distilled white vinegar can kill some mold species, though it’s less effective on porous surfaces. Hydrogen peroxide is another DIY alternative that kills mold and lightens stains, but it can bleach fabrics. Commercial alternatives include products like Mold Armor, which offers a bleach-based formula similar to RMR-86, and Benefect, a botanical disinfectant that is non-toxic like Concrobium.
If you’re dealing with a recurring problem, consider adding a moisture absorber or a dehumidifier to your routine. These don’t kill mold but prevent it from growing. For HVAC systems, specialized mold treatments for ducts are available. Always research the product’s compatibility with your surfaces and your safety needs.
For large infestations (more than 10 square feet), the EPA recommends hiring a professional mold remediation specialist. DIY products may not fully address the problem and could spread spores.
It’s not recommended. RMR-86 contains bleach, which can fade or discolor fabrics. For fabric, use Concrobium or a fabric-safe mold cleaner.
Concrobium kills mold on contact, but you may not see the visible results immediately. It typically takes 24 hours for the mold to die and dry out. For heavy mold, you might need to apply it multiple times.
Yes, but with precautions. Ensure the area is well-ventilated, and wear protective gear. Avoid using it in enclosed spaces without airflow, and keep children and pets away until it dries.
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