It could be any number of aquarium diseases. take a sample of water and the next fish that dies to your local aquarium store and have them looked at.
Ammonia comes from fish waste.
check the pH balance for ammonia
It would die. The ammonia would kill the fish if amounts were elevated.
Sometimes fish die in aquariums when the ammonia level is too high. I recommend taking a sample of the water to a pet store to have it checked for anything wrong. I had fish dying and took mine to have it checked. When I got the levels water problems fixed my fish stopped dying. It could be from high ammonia levels, not enough oxygen, not the right temperature, or a disease or parasite
Ammonia levels should be at zero. Ammonia is never safe to have in an aquarium especially new fish. Transporting a fish generally causes some stress for them and with the addition of a water problem in their new home it could prove fatal. If this is a brand new tank it would be wise to cycle it fully before adding a fish.
Ammonia is a base. To fix it, perhaps try adding buffer to the water. Just as a side note, the ammonia is actually a product of the fish. Fish pee pure ammonia because of the abundance of water in their system.
Nitrogen Cycle occurs in the aquarium.Fish produce ammonia which is toxic. In a well established aquarium, Some beneficial bacteria will break down the ammonia into nitrite, and a second species of bacteria will break down nitrite into less harmful nitrate. The whole process of converting ammonia into nitrite and then into nitrate is called nitrogen cycle.Although, only well established fish tanks have this nitrogen cycle going normally.For new aquariums, fish keepers must do fishless nitrogen cycle before they add any fish at all, or the fish will risk dying to ammonia poisoning due to insufficient amount of good bacteria. The whole fishless nitrogen cycle process can take 6~8 weeks.
The fish are drinking it. Get rid of the fish
They do not "show" balance of nature. What could be happening is, your planted aquarium could be a "balanced aquarium" or be in the process of becomming one. In a 'balanced aquarium' the living creatures (fish etc) produce waste products. These products decay and become poisonous (Ammonia). Without a natural balance of other organisms (Bacteria) the living creatures in the tank would all be poisoned by the ammonia. What happens in a balanced aquarium is. The Waste Products produce Decay which produces (deadly) Ammonia. Aerobic bacteria convert Ammonia into (deadly) NitrIte and then into (harmless) NitrAte. The plants can then use up the NitrAte and in the process of photosynthesis, produce Oxygen, some of which is used up by the fish etc. In todays aquaria most of this 'Ammonia to Nitrate' conversion is carried out in a filter that has been 'cycled'. Cycled simply means that the filters' media have suffucient aerobic bacteria to perform this Ammonia to Nitrate 'conversion'.
Yes. When fish food(ex. tropical flake) sits for too long, it turns into ammonia, a very poisonous substance for fish.(and everything else too!) To prevent your fish from dying from ammonia, clean your tank about every 2 months.
No, leave the tank for several days, then get your water tested for ammonia and nitrite. Depending on the results, either get a FEW new fish, or let the aquarium run until the ammonia and nitrite are gone.
Check the nitrates. Clean the tank. Condition the water. Treat for disease. Remove fish that seem unhappy or distressed or sick. That's all i can give you maybe you need to take logs of everything you do and check with the local peet shop to ensure everything is correct.