Aquatic ich is an invasive parasitic flatworm that can infect freshwater fish and other aquatic animals.
It is the most common form of ich, and it has been reported to cause significant economic losses in aquaculture.
The parasite enters through the gills or skin and attaches itself to the host’s body.
The adult worm forms a cyst around the site of attachment and releases eggs into the surrounding water column where they are ingested by free-swimming larvae.
These larvae then attach themselves to the mucus lining of the intestine and develop further until they reach adulthood.
Adult worms may live for up to two years.
Whilst this might sound like something out of a horror movie, it can happen at home inside your aquarium.
So, let’s take a look at what it is, how to avoid it, and what can help to remove it.
The Life Cycle Of An Ich
The life cycle of ich begins when the parasite hatches from its egg.
After hatching, the larva moves towards the surface of the water and attaches itself to the substrate with a sucker on its head.
This movement is called “crawling”.
The larva then secretes enzymes which digest the tissue of the substrate. As the larva grows, it develops a mouth at one end and a tail at the other.
When fully grown, it will have reached about 5 mm in length. From this point onwards, the larva becomes known as an ich.
The ich feeds on the blood of its host. If the host dies, the ich will move onto another animal. Once infected, the ich cannot be cured.
Prevention & Treatment Of Ich
There is no cure for ich once the infection occurs. Prevention is therefore key to controlling the spread of the disease.
A number of methods exist to prevent the introduction of ich into new areas. They include:
- Preventing the introduction of ich eggs into new environments.
- Using only healthy stock.
- Monitoring all incoming fish for signs of ich.
- Testing fish before releasing them into a new environment.
- Regular cleaning of tanks.
- Using UV light to kill ich.
UV Light Snd Ich
UV light kills ich by damaging their DNA. In order to do this, the light must pass through the water.
Therefore, if you want to use UV light to treat your tank, you need to place it above the level of the fish.
You should also ensure that the light does not shine directly into the eyes of the fish.
In general, UV light is used to disinfect water. However, it can also be used to sterilize surfaces such as glassware and equipment.
How Does UV Work?
When exposed to ultraviolet radiation, some molecules absorb the energy of the photons.
The absorbed energy causes chemical changes within these molecules.
For example, the oxygen molecule absorbs the energy and breaks down into two atoms of oxygen. The hydrogen atom remains unaffected.
This process is called photolysis. Photolysis is what happens when UV light passes through the water.
The UV rays damage the DNA of the parasites and stop them from reproducing.
What Types Of UV Lights Are Available?
There are three main types of UV lights available; low pressure mercury lamps, medium pressure sodium lamps and high pressure xenon arc lamps.
Low Pressure Mercury Lamp
A low pressure mercury lamp produces a narrow beam of light.
It has a very short wavelength and is best suited to killing bacteria and algae.
Low pressure mercury lamps produce a broad spectrum of wavelengths.
Medium Pressure Sodium Lamp
A medium pressure sodium lamp produces a wide beam of light. It is ideal for killing algae.
Medium pressure sodium lamps produce a broad spectrum similar to that produced by low pressure mercury lamps.
High Pressure Xenon Arc Lamp
A high pressure xenon arc lamp produces a narrow beam. It is suitable for killing bacteria and viruses but not algae.
High pressure xenon arc lamps have a long wavelength and are therefore unsuitable for treating aquariums because they would cause excessive heating of the water.
UV Light In Aquariums
The most common type of UV light used in an aquarium is the low pressure mercury lamp.
This type of lamp emits a broad spectrum of wavelengths between 250 nm and 400 nm.
These wavelengths are too large to penetrate the skin or the cornea of fish. As a result, the lamp cannot be used to kill ich.
The lamp will however kill other organisms which may be present in the tank.
If there are any problems with the lamp, it will give off an orange glow.
The second most popular type of UV light used for aquariums is a medium pressure sodium lamp.
A medium pressure sodium lamp produces light at a wavelength of about 590nm.
This wavelength is close enough to the absorption peak of chlorophyll so that it can still be used to kill algae.
The third type of UV light used to treat aquariums is a high pressure xenon arc.
This type of lamp produces light at a much shorter wavelength than the previous two types.
As a result, it can only be used to kill bacteria and viruses.
Why Is Ultraviolet Light Used To Treat Aquariums?
UV light is used to treat aquariums because it kills microorganisms and algae. It does this by damaging their DNA.
When a microorganism dies, its ability to reproduce is stopped.
Why Do I Need An UV Sterilizer In My Tank?
An UV sterilizer is needed if you want to keep your aquarium clean. Fish and invertebrates need sunlight to survive.
They also need to breathe air. Both of these things require oxygen.
Therefore, if you do not provide sufficient levels of oxygen in your aquarium, then the fish and invertebrates will die.
How Does An UV Sterilizer Work?
An UV sterilizer works by producing ultraviolet (UV) radiation. UV radiation is invisible to humans.
However, it is absorbed by organic matter such as algae and bacteria.
Once inside the organism, the radiation damages the DNA of the microorganisms.
This stops them from reproducing and eventually causes them to die.
What Are Some Of The Benefits Of Using An UV Sterilizer?
Using an UV sterilizer provides several benefits. Firstly, it prevents the growth of unwanted organisms in the aquarium.
Secondly, it helps to maintain healthy conditions within the aquarium.
Thirdly, it reduces the risk of diseases spreading throughout the aquarium.
Finally, it increases the lifespan of the fish and invertebrate species.
A UV sterilizer is essential if you want to keep a clean aquarium. It will help to prevent the growth of harmful organisms and reduce the risk of disease.
Whilst ich cannot be cured, you can prevent it. So always make sure you take measures to reduce the risk of your aquarium suffering with ich.