Chlorine poisoning
Chlorine and its compounds enter the aquarium from tap water, where it is used for disinfection. This happens only when the water does not undergo pre-treatment, but is poured into the fish directly from the tap.
Currently, there are many water treatment products that effectively remove not only chlorine, but also other gases and heavy metals. They are supplied to almost all professional pet stores, and are also available on specialized online stores.
An equally effective way to remove chlorine is to simply settling the water. For example, fill a bucket, submerge a spray stone in it, and turn on aeration overnight. The next morning, water can be added to the aquarium.
Symptoms:
The fish become pale, a large amount of mucus is secreted, reddening of some parts of the body occurs. Changes in behavior are observed – they swim chaotically, they can collide, rub against interior items.
Treatment
Move the fish to a separate tank of clean water immediately. In the main tank, either add chlorine removal chemicals (available from pet stores) or do a complete water change. In the latter case, you will have to wait again for the completion of the nitrogen cycle.
