Abnormal fish behavior

11 مارس 2020
Abnormal fish behavior


  • Scratching/flashing/flicking:

The term flashing is the aquarium-speak definition of “itchy fish.” when a fish is flashing, he is trying to scratch himself by rubbing or banging on things. There can be a number of reasons why a fish might flash, but parasite problems are a common cause and can be a good place to look first. Freshwater or saltwater Ichthyophthirius multifiliis (Ich) can cause flashing, so look for tiny white specks on your fish; this is the classic symptom of Ich and your fish may be flashing because of the irritation. Ich is a bit like fleas in mammals; the parasite has a somewhat complicated life cycle


  • Air gasping position:

If your fish look like they are gasping for air at the top of the aquarium, this is a sign that either your water quality is poor or there is not enough dissolved oxygen in the water
The low levels of oxygen are mainly due to a lack of aeration or poor water quality, which can then cause the fish to stress.  This stress slows their immune systems and leaves them vulnerable to parasites and disease

Fish need different amounts of oxygen depending on the season.  In winter they need less because they are hibernating but during summer months, when they are most active, they demand a higher amount.  With warmer temperatures, water holds less dissolved oxygen leaving aquatic life competing for the little that remains.  This is why supplemental aeration is so important.  You can add pond plants, which naturally release oxygen into the water during the daytime.  You should also keep your pond pumps and fountains running.
You can also add an aerator, a waterfall, or spitter to make sure the oxygen levels are sufficient 

Poor water quality can also attribute to fish gasping for air at the pond’s surface, so you should also check your filtration system and use a test kit to test levels of ammonia and nitrite.  Using pond cleaner tablets will add beneficial bacteria and a water clarifier and chlorine remover will help to ensure excellent water quality for healthy fish

If all water parameters fall within healthy levels, other factors can be reviewed. The presence of large amounts of plants or algae in a system can drop the oxygen levels to a critical point in summer and in heavily planted ponds some overnight aeration or extra water movement may be necessary to drive off carbon dioxide and increase dissolved oxygen content


  • Laying on the bottom:

If your fish is spending lots of time at the bottom of the tank, it may be normal behavior. Many fish, like catfish, are bottom-feeders and spend their time there. Fish also often sleep at the bottom of their tank. If your fish’s activity, however, does not seem to fit either of these reasons, and he looks tired and listless at the bottom of the tank, it may be a sign of disease caused by: stress , loud noise , rapid temperature changes, non-compatible fish in the fish tank, fish diseases , overcrowded fish tank

Laying on the bottom can be also sign of  water quality imbalances
significant pH level change, raised ammonia level, high nitrites level, high nitrates level, high water hardness, low oxygen level


  • Listlessness:

tired and lethargic fish can be due to many factors. Most common reason is improper water temperature. If water is too hot or too cold, your fish will be very inactive. Other causes may be overfeeding or improper water quality


  • erratic swimming:

 can also be caused by poor water quality: include incorrect pH levels , ammonia buildup, high amounts of nitrates or nitrites, or temperature changes. An aquarium that is overstocked with too many fish can cause water quality problems that may be manifested by erratic swimming. Even a sudden change in water parameters can be problematic

Erratic swimming can also be caused by skin or gill flukes, which can be a little harder to detect. A fading in your fish's color or change in the appearance of his gills—such as excessive visible mucus


  • Fighting Fish:

If your fish are fighting, it generally means that they are not a compatible fit to be housed in the same aquarium. Many fish are naturally aggressive and will defend their territory to the death. Before stocking your aquarium, you should do research on which types of fish are compatible with others together. Here are some tips on keeping a peaceful aquarium :

  1. Try to vary between both top-feeders and bottom-feeders
  2. Make sure your aquarium is large enough to accommodate all of your fish
  3. Change the scenery periodically and always before adding new fish, so as to eliminate territorial claims
  4. Have a good variety of different types of fish


  • whirling pattern of swimming:

The abnormal swimming behavior in salmonids infected with Myxobolus cerebralis has commonly been attributed to peripheral neurological effects of invasion of cartilage by the parasite

These fish displayed a behavioral syndrome consisting of

  1. sequences of tight turns (whirling)
  2. periods at rest in which the tail was elevated higher than the head
  3. episodes of postural collapse and immobility. In spite of these behavioral disturbances, the infected fish showed virtually no behavioral indications of impaired vestibular system function, such as difficulty maintaining an upright posture