How to Get Rid of Silverfish – Natural, Herbal, and Chemical Treatment

Silverfish (Lepisma saccharinum) are of the order Zygentoma. The name silverfish is because of their property of fish-like movement appearance and silvery light grey color. Their diet consists of sources of carbohydrates like starches and sugar.

They are nocturnal insects of about 13-25 mm in length. They appear like fish due to their tapered abdomen at the end. The younger ones are whitish and develop grey metallic shine on hatching. With one terminal filament at the abdomen and two long cerci, they possess two compound eyes.

Some species like Apterygota are wingless, have long antennae, and move with fish-like wiggling motion. They can regenerate filament and antennae in two to four weeks if lost. The life span of silverfish is up to three years. The silverfishes are very good runners, but only on horizontal surfaces. They also avoid light mostly.

1.1    Distribution  

Silverfishes are cosmopolitan species and are found in the Americas, Africa, Eurasia, Australia, and other parts of the Pacific. They need a humidity level of about 75% to 95% for inhibition. One can find them at the basements, attics, bathtubs, sinks, kitchens, showers, classrooms, and even in old books, or in urban areas.

1.2    Life Cycle and Reproduction  

There is an interesting process involved in reproduction. The male and female stand face to face with their antennae touching in the first phase. In the second phase, the male runs away, and the female chases him. In the third, they stand beside each other head to tail and the male lays his spermatophore which the female takes in her body through ovipositor to fertilize the eggs.

The female can lay up to 60 oval-shaped, whitish eggs at a time that takes about two weeks to two months to hatch.

1.3    Etymology and Nomenclature  

Due to the tendency of silverfish to eat starchy foods, the scientific name Lepisma saccharinum was given by Carl Linnaeus in his 10^th edition of System Naturae in 1758. They eat food as dextrin which is rich in carbohydrates and protein. The common names have come from their specific metallic appearance and fish-like shape. The common names came into practice from 1855. The common nomenclatural gender of Lepisma was treated as feminine by most of the authors (1957).

However, in 2018, the International Commission of Zoological Nomenclature stated the gender of Lepisma (and all similar) as neuter, post-ICZN Article 30, which saw the changes in the spelling of many well-known species, including Lepisma saccharinum.  

1.4    Types of Silverfish –
 
There are around six types of silverfish known, of which are listed as follows –

• Bristletails – Though bristletails are referred to as silverfish, they are members of the microcoriphia order of insects.
  
  There are about 300-400 species in the world, of which around 24 species are found in the United States alone. They have cylindrical bodies and are observed with grassy or wooded habitats living usually under decaying leaves, bark, in rocks, or under stones. These species lack wings.

• Common Silverfish – They are also wingless and about ½ inch in length. They seek indoor areas like bathrooms, basements, and kitchens. They are nocturnal and prefer to hide during the day to avoid light. The common silverfish life span is about eight years.

• Four-Lined Silverfish – Their scientific name is Ctenolepisma quadriseriata. The four-lined silverfish have four dark lines on their stomach and are a little longer than common silverfish. They prefer to live in flowerbed mulch and under roof sheds. They can be found in attics, if they enter indoor.

• Gray Silverfish – These are Ctenolepisma longicaudata with mostly dark or gray color. They live in attics, crawl spaces, and bathrooms.

• Firebrat – Their scientific name is Thermobia domestica with a yellowish body. Surprisingly, they prefer to live around a hot temperature of about 90 degrees or more, such as furnaces and fireplaces.
  
  Thus, they can also be found in the insulation of heating pipes. They mostly feed at night.

• Jumping Bristletail – They are gray and silver and can grow more than ½ inch. They live under decaying leaves, bark, rubble, and stones. The scientific name is Pedetontus sp.

1.5    Habitats  

Silverfish can survive a long time without food and water but for that, they will need a favorable environment. They like to live in high humidity areas with humidity as high as 70 to 90 percent and room temperatures around 21 to 29 deg centigrade. You can find silverfish almost everywhere in the house including attics, garages, basements, living rooms, bathrooms, bedrooms, and even on roofs. The roofs are the most favorable for them to lay eggs and breed because of the perfect atmosphere of high temperature and humidity for their survival.

During summer, they would get umpteen of moisture, cellulose, dead insects, and starch. In the longer term, they can get entry into the house through the insulation. We have seen that some silverfish live even in steam pipe insulation.

Silverfish contaminate the offices, libraries, and stores in particular. From the outside, they enter the building through carton boxes used as packaging material for almost everything. They enter through books and cardboards from outside. Once they are in the building premises, they reside in places like roofs initially and then, move down.

This movement will be in search of food and once they locate the food, they will always remain close to that source. They will breed in different areas like wall voids, under subflooring, behind wallpapers, etc. They feed on food like oat and flour too but mostly eat on paper, clothing, or glue of the books or carton boxes. They are known to be cannibalistic and like to get their favorite protein food from dried beef or injured beef.

The female silverfish lays one to three eggs per day. Under favorable conditions, the development takes in three to four months and under unfavorable conditions, it may take up to two to three years. Most species of the silverfish have a life span of three years.

1.6    Silverfish Habits  

• Silverfish can move throughout the building. They are fast runners too.
• They always stay close to their food source.
• Their life-cycle called gradual metamorphosis includes three phases against most of the insects with a four-stage life-cycle (complete metamorphosis).
• Silverfish can lay eggs at any time during the year. The eggs hatch in 19-43 days. It takes three to four months for silverfish egg to adult phase.
• Silverfish are nocturnal but can remain active in an area that is dark and this can be a problem year-round.
• They are poor on a smooth and vertical surface and once trapped in places like sink or glass jars, they are unable to climb back to the top.
• Silverfish attack paper and clothing and are a threat as they can damage many important documents and clothes. They can also infest the area, if one has spilled drink somewhere.
• They feed on cellulose and carbohydrates, so, they will attack all sources of these two ingredients.
• Silverfish molt throughout their life-cycle. Finding the cast skin of silverfish in the house is the sign of the infestation.
• If you find irregular small holes in fabrics or linen, it is a sign of silverfish infestation. As they eat glue, you may also find irregular holes in the wallpapers in your house.
• Firebrat, a species of silverfish, extensively feeds on rayon and most of the silverfish leave a yellow stain on the fabric. This yellow stain will be their faeces usually.
• Silverfish live in any dark and humid places in the house.
• Outdoors, one can find them in nests. It is not necessary that they live in their nest as they can live in a bird’s nest too.
• They can accommodate themselves under tree barks and mulch easily. 

2.      How to Get Rid of Indoor Silverfish?

Silverfish are known to live eight years and they also reproduce very quickly. However, the severity of the infestation will not be known as they are active at night and like to live very secretly. If you are regularly taking care of your magazines, newspapers, and old clothes and fabrics, you may not have the infestation indoors.

If by chance, any place with such material remains neglected, then, there is a chance of infestation to occur.

2.1    Natural Home Remedies to Get Rid of Indoor Silverfish  

Since the silverfish are not so dangerous to humans as they do not bite or spread disease, one can get rid of them without being in a state of panic. One or two days here and there won’t harm anyone of the family.

You can adapt some easy methods to get rid of them –

1. Diatomaceous Earth – The diatomaceous powder is made of grounded fossils with jagged edges. You can sprinkle the powder around the sink, cupboards, and other areas which are mostly moist.
   
   When the silverfish tries to move through this, it kills them.

• Boric Acid – Spread a little amount of boric acid powder (out of children’s and pet’s reach). Its toxicity towards the insects is highly effective to repel or exterminate them quickly.

• Sticky Insect Traps – The traps can catch the silverfish that try to crawl through small gaps. One has to just place the sticky traps at the right places, so, that the silverfish can be trapped easily during their movement in the house.

• Close the gaps – It is better to fill all the gaps which have arisen due to wear and tear.

• Raise the barriers – One can place gravel or chemical barrier between the outer area and wall of the basement. The gravel will not allow moisture and thus, will keep the silverfish away.

• Protect the food source – Always ensure to keep the food in air-tight containers. Keep house neat and clean. Work on the management of paper products has to be done keeping in mind the sources of cellulose.

• Glass container trap – It is a very simple method to catch silverfish. You just have to put some starchy food substance in a glass jar and apply the tape from outside. As the silverfish enters inside to get the food, it won’t be able to get out again because of a smooth glass surface.

• Wet newspaper – Roll a newspaper and sufficiently wet it. The silverfish, being attracted to the moist things, will nest inside it. In a few days, you can burn or throw away the infested newspaper along with the silverfish.

• Cedar Oil – Use cedar oil with water in a sprayer or diffuser. The strong-smelling aroma will effectively repel the silverfish. 

1. Bay leaves – The oils in the bay leaves sends a strong repellent smell that is hated by the silverfish and most of the other insects.

1. Remove items with adhesives – The items like cardboard boxes, stack paper, and laundry should be kept well outside the house. The adhesive attached to it always attracts silverfish due to their cellulose contents.

1. Manage food items properly – The food items must be kept in sealed containers and the area of food preparation and storage should be treated with a HEPA vacuum that is capable of sucking the silverfish and their eggs to stop reproduction and multiplication.

1. Treat with caulking – Even the smallest of gaps has to be treated by caulking them completely. This will eliminate the chances of silverfish laying eggs there.

2.2    How to Get Rid of Indoor Silverfish with Pets in House?

Silverfish are neither stingers nor biters on both humans and pets. Since they are also not known to carry any kind of disease, it is safe to handle their infestation. The only risk is the debris they create can be allergic. The molted skin might be an allergen to some people or pets.

Tropomyosin, a protein in the exoskeleton, if combines with other allergens found in common indoor pests like dust mite, can produce allergic results. 

2.3    Chemical Treatment to Get Rid of Indoor Silverfish  

The silverfish infestation located with the signs of holes, etches, or notches on surfaces, can be treated by using some insecticide chemicals.

1. Synergized Pyrethrins – This is an environment-friendly chemical approved by the USDA and can effectively control the insects. This chemical quickly decomposes in the environment and is very safe to use.

• Bifenthrin – Bifenthrin is used on a large scale to get rid of many invasive insects and pests. Though it is not a quick kill chemical and takes around 10 minutes to effect, it leaves a long-lasting effect.

• Cyfluthrin – It is a common pyrethroid insecticide. It is a complex organic compound and sold in the form of a mixture of isomers. It is highly toxic to fish and invertebrates but less toxic to humans. It kills a wide variety of household pests.

• Tetramethrin – It is the synthetic insecticide of the pyrethroid family. It comes in the white crystalline form and its melting point is about 65-80 deg centigrade. It affects the nervous system of the insects and pests.

• Phenothrin – It is also called sumithrin and d-phenothrin. Along with silverfish, it is also used to kill other insects like fleas, ticks, and head lice in humans. It is used as the active ingredient in aerosol insecticides.
  
  It is low in toxicity to humans but can trigger skin reactions and sensations in sensitive people.

• Dekko Silverfish Paks – This contains 20% boric acid. It can be approximately applied 2 oz. per 100 square feet and is best to use in places like basements, attics, book-shelves, carpets, rugs, drawers, etc. of households.

• Springstar S206 Trap – This can be used for silverfish as well as spiders for trapping them.

3.      How to Get Rid of Outdoor Silverfish?

As we now know that silverfish likes to live in moist environments and they can be found under stones or rocks, we can plan the methods to get rid of them accordingly. They can be living even in bird nests, or rodent burrows.

3.1    Natural Home Remedies to Get Rid of Outdoor Silverfish

We can treat the silverfish infestations with natural as well as chemical methods. While some methods are useful indoors, the same won’t be applicable outdoors.

So, it is essential to plan them properly. There are some common ingredients used to get rid of most of the insects and some methods are pest-specific. We can see below methods –

1. Boric Acid – It is a well-known ingredient used widely to get rid of most insects. The two major effects of it are its smell and its dehydrating property. The smell douses the insects and on contact with this powder, their exoskeletons get dry, and eventually, it leads to the death of the insects.

• Diatomaceous Earth – Diatomaceous earth makes the silverfish thirsty. The dehydration and the sharp edges of individual atom results into the death of the silverfish. The diatomaceous earth is fossilized material of the remains of algae called diatoms.  

• Cedar Shavings – Silverfish are repellent by the generally fine-smelling cedar. You can use the cedar shavings in your basements which mostly are a mess of the places. You can also apply the mix of cedar oil in the cracks and crevices to block the egg-laying places of silverfish. 

• Cinnamon – The silverfish cannot stand the smell of cinnamon. You can place the cinnamon sticks around the places of infestation. Cinnamon smell will repel the silverfish quickly and it will not even reappear.

• Citrus Fruits – Citrus plants have a very strong smell and they act as insect repellent too. One can use orange or lemon peels to get rid of silverfish around the house. You can place the peels in the affected area, even under plants, to get the desired output from this method.
  
  Ensure to replace the peels periodically.   

• Moth balls or Naphthalene balls – The smell of the naphthalene balls is intolerable to the bugs, though for human beings, it is good. You can keep the naphthalene balls in the dark, moist places so as to repel the silverfish. You can place it in shoe racks outside the porch.

• Cucumber peels – Cucumber smell is hated by silverfish, hence, you can use the cucumber peels to get rid of them. It is effective if you place them anywhere near the activity of the silverfish. This works both indoor and outdoor and gives similar results as that of cedar or cinnamon.

• Cloves – Cloves contain Eugenol which is an insecticide used widely. Using the whole clove gives better results as it continuously keeps generating a powerful aroma. One whole clove in the cracks or crevices, dark and a damp place, near drains and holes, is sufficient enough to keep silverfish at bay.

• Table salt – One of the most easily available home remedies is to use table salt. This will help you get rid of silverfish naturally.
  
  As it is a very common thing the pests eat, they suffer and die of dehydration. It is a punitive material that reacts when bugs eat it. You can sprinkle the salt around the house and keep them away.

1. Flour mix – Make a paste of flour and water. This paste can be used as bait paste. Apply this on cards from both sides and dry it. You can place these at the places of silverfish activity.

3.2    Chemical Treatment to Get Rid of Outdoor Silverfish

Apart from the natural remedies, you can try the chemical treatment if the infestation is higher. Following insecticides can be used –

1. LambdaStar UltraCap 9.7 – This is a very good spray insecticide which can be used on walls and compound. This product is odorless also and it does not leave any film.

• Cyper WSP – This is a wettable powder formulation and it leaves a slight film against the dark surfaces.

• Cimexa Dust – This is an insecticide dust and can be applied to attics. This gives a six months long protection to the areas of application.

• D-Fense Dust – This dust will be effective on the dry areas. While applying this, you can use a duster called Dustin Mizer. This will help you serve a large amount in a quick time.

• Intice Granular Bait – It works great against silverfish, cockroaches, and crickets. Sprinkle this out in a self-contained bag, in the areas where you feel silverfish are hiding such as crawlspaces and attics.

• PT 221L Residual Insecticide Aerosol – This contains a special tip that helps you to easily reach behind baseboards or corner trails of the silverfish when they move. It also helps you to get rid of silverfish behind the wallpapers of your house.

• Pro-Pest Silverfish Traps – This is a ready-to-use product and it helps protect the books and antique pieces in the libraries.  

3.3    How to Get Rid of Silverfish in Your Yard?

Getting silverfish infestation in your yard is a sign of an increase in moisture content in the area. There must also be many places where silverfish would like to harbor. Such areas of dark and moist atmosphere must be taken care of, particularly in the rainy season. In the rainy season, you will find a lot of silverfish if you don’t take preventive measures to avoid them.

• Do not leave any kind of litter in the yard area, specifically stones and leaves as these are their favorite hiding places.

• Remove all the clutter from the unused corners in your yard. Move the things which are not in use for a longer time and clean and disinfect the area with proper insecticide.

• Do not leave stagnant water anywhere in the yard. This will provide a perfect platform for silverfish to hide below stones or leaves.

4.      How to Get Rid of Silverfish from Trees?

If you want to keep silverfish out of your property, along with some easy remedies, you can also plan long-term methods such as planting. This will solve two purposes, keeping them away from trees and preventing them to enter your area. There are several plants that are naturally insect repellent and having them in your garden is more of an advantage than the disadvantage of attracting some pests.

4.1    Simple Ways to Get Rid of Silverfish from Trees  

We will see which plants help keep the silverfish away –

• Camphor– It can be used in its natural form or one can make an insecticide out of it.
• Rosemary – It is another great silverfish repellent. The method is very simple. You have to place sachets of dried or fresh rosemary around the area of silverfish infestation. This will drive the silverfish away from your home.
• Costmary Springs – These are often referred to as bible leaves as they are used as bookmarks in the bible. The smell of costmary spring plant keeps the silverfish away.
• Cucumber – Peels of cucumber helps to get rid of silverfish. An easily available method where you can simply place peels around other trees to shove away the silverfish from them.

5.      How to Find Silverfish Nests?

Silverfish are attracted towards the moisture; they eat insects, live on carbohydrates. You can never find their nest in open. They always nest in dark, moist areas indoor and outdoor. As silverfish are nocturnal, you won’t suspect any infestation till you find one in the darkest area of the house. You can find them only if you put on light.

You can find the silverfish nests outdoors under rocks or tree barks at moldy places. Silverfish also nest in other insect nests like termites, birds, and even rodents. They can nest in buildings at crawling places. When the weather outside gets cooler, they prefer to move indoors to get their desired temperature of about 70 to 80 degrees Fahrenheit.

Indoors, you can find them nesting at the places like basements, laundry rooms, kitchens, heating pipes, and water pipes which are usually of high humidity. They lay eggs and nest in cracks and crevices of these areas. Kitchen cupboards, attics, and closets are the other places of their attraction as they can get paper and clothing to feed on because of their carbohydrate sources.

6.      How to Treat Silverfish Bites?

Silverfish do not bite human beings. This is because their jaws are too weak to break human skin. However, they can make a mess of your property by chewing and destroying your papers. They like any material that contains cellulose and papers are a full source of cellulose.

FAQs

How to Get Rid of Silverfish under Pavers?

Inspect the pavers and caulk any smallest of the cracks and crevices observed. This is the place where silverfish would like to lay the eggs.

How to Get Rid of Silverfish around Pool?

Sprinkling the boric powder around the pool area is always a better solution as already you will be adding it to pool water too. This will simplify the method without having to do additional effort.

How to Get Rid of Silverfish with Wings?

Silverfish do not have wings; however, they are expert in running faster. You can trap those in a glass jar by placing it on their path of activity. Once inside, they cannot climb out back as they are poor on vertical smooth surfaces.

How to Get Rid of Giant Silverfish?

As such, silverfish are not threateningly in giant-form; however, the biggest species can be trapped on the sticky traps or in the glass jar. You can also kill them by using boric powder or insecticide spray.

How to Get Rid of Silverfish under Carpet?

This creature silverfish are not known to infest carpets but they can use it as a hiding place during the day. Using a vacuum and keeping the carpets humid-free can do the job. Vacuuming is a very effective way to get rid of most of the insects indoors.

How Vegans Get Rid of Silverfish?

Vegans will always vow on catching and leaving pests away from their houses. Usually, they won’t kill until it is making a high degree nuisance. 

How to Get Rid of Silverfish in Refrigerator?

Silverfish are known to survive mostly in higher temperatures. The silverfish entered in a refrigerator can’t survive longer and if it is in the initial phase, it cannot grow to the next phase. So, there is no big harm but yes, it will look nasty in the refrigerator if you do not remove them from there.