Here, We are going to discuss that, why do fish die in an aquarium?. Inconsistency of the recommended water parameters is a common cause of fish death. Tap water contains too much chlorine and other chemical elements; if you pour it directly from the tap, your pets are unlikely to survive. Firstly, the water must be defended, secondly – filtered, thirdly – aerated, and sometimes you have to distill and use chemical reagents.

Keeping each type of fish requires certain indicators of acid-base balance, salinity and hardness. Which must be observed in order for them to be healthy and reproduce successfully. Change the water on time, renewing it daily at a time, but no more than 30%. As a result of the life of the inhabitants, the water in the aquarium is quickly saturated with nitrogenous compounds and they are the most common cause of the death of fish.
Aquarium Temperature
Water temperature is also a major cause to fish die in an aquarium. As this is important for cold-blooded pets. A difference of even one degree with the recommended one is felt by fish in about the same way as people. A change in the air temperature of 10 degrees. Even if you have poured water into the aquarium that is comfortable for this breed. Everything can change quickly due to temperature fluctuations in the living room. For example, due to turning on / off the heater, melting the stove or fireplace. It is necessary to place a thermometer in the aquarium and monitor the temperature in it as often as possible, taking measures to optimize it.

Read More About Fish Diseases: Fish Diseases
Aquarium Lighting
It is also unacceptable to ignore the observance of the light regime. So, the daylight hours of many tropical fish should last at least 10 hours. Therefore, in winter, when the daylight hours are short, additional lighting must be turned on. Failure to comply with this rule makes it difficult for many fish to digest and can lead to their death. Do not place the aquarium near a window, as direct sunlight can cause water to bloom.

Aquarium Population
The viability of fish often depends on the qualitative and quantitative composition of the aquarium population. The point is not only that certain types of fish are predatory and can eat other inhabitants of the aquarium. Even a small fish needs at least 3 liters of water. If you overpopulate the tank with fish or put too many plants in it. The fish will die from ammonia poisoning or lack of oxygen.
Choose an aquarium population with similar conditions of keeping and observe the measure. Do not try to cram as many pets as possible. For example, schooling mobile zebrafish do not get along with scalars and goldfish, and barbs and cockerels eat the lush fins of neon’s.

If the Fish Began to Die After Being Hooked Up By a New One, She Probably Brought Some Kind of Infection
And if the newcomer herself died, the reason is in the wrong adaptation. Each newcomer should first be placed in a separate vessel with the most favorable water for him. Then every quarter of an hour add water from the aquarium until it takes up three quarters of the entire vessel. If the fish is feeling well, it can be populated into a common tank. Cold-blooded diseases are a separate big topic, you should know them and, if necessary, treat your favorites.
Do not put fish into the aquarium soon after filling with water. First, it is launched with operating equipment (filter, aerator, heater, lighting elements), but without fish, and they wait about a crescent until biological equilibrium is established. In this case, at first, the water must become cloudy due to a bacterial outbreak, then it must be purified without outside interference.
Food for Aquarium Fish
The food should be complete and varied. If you give only dry food to the inhabitants of the aquarium, their stomach or intestines can become inflamed. Which for such fragile creatures is almost tantamount to death. Be sure to include live, frozen, and herbal ingredients in your diet. Daphnia, koretra, bloodworms, brine shrimp are suitable for feeding most aquarium fish.

Give them in small portions several times a day, preferably at the same time. Throw food while the fish greedily grab it, and immediately stop feeding if they stop picking up food and collect the remains from the bottom with a hose. In this case, the fish will be healthy, and the aquarium will not become clogged.
Study special literature to prevent fish die in an aquarium and apply the knowledge gained so that your fish feel good and live long.