Boric Acid The most effective poison for use against silverfish is boric acid.
This substance is present in many plants such as fruits but only in tiny quantities.
When concentrated, it is effective as a poison.
How Does It Work? When silverfish eat boric acid, it plays havoc with their metabolism and they quickly die.
This substance is very bad for them as well as most other insects.
In fact, the powder form of this acid is also an absorbent.
So when ingested, it literally soaks up all the moisture out of the insect, from the inside! Believe it or not, but boric acid can also kill in a third way.
It is highly abrasive and can literally tear apart any silverfish whose bodies rub against it.
Is It Easy To Get Hold Of? This silverfish poison is really easy to get hold of.
It comes in many forms.
The most basic is as a powder, usually at a strength of around 20%.
I recommend you start there.
If you have a more serious problem then you can always get something a little stronger although you may have difficulty finding anything other than the standard 20% strength.
Pests such as the silverfish are not always automatically attracted to boric acid so people will often mix bait with boric acid.
You can even buy ready made traps that are nothing more than cardboard and boric acid.
When the silverfish eat the cardboard, they are poisoned and die.
What About Alternatives? This silverfish poison works great and is considered safe for home use against pets.
However, some scientists have discovered that it can be harmful if you are repeatedly exposed to it.
If you have kids or pets then you might not want to use boric acid.
You can buy different forms of powder.
Unfortunately, they are not poisonous but they will still kill due to their abrasive and absorbent nature.
One is derived from plant material and the other is derived from mineral rock.
As for traps, you can also make your own out of a glass jar with some bait inside it.
Wrap tape around the outside to give the silverfish something to climb up.
Once they are in the jar, they will never be able to climb out again.