To change or not to change
If the tank dies only one fish but the water looks clean, no change necessary because after changing the water need to wait for the restoration of ecosystems and biological balance. So you can simply top up fresh water, renewing the old. If the fish died from an infectious disease or has been in the aquarium for several days, the water should be replaced, washed the aquarium.
When adding fresh water in the aquarium must be not less than one-third of the old water – this fresh water should have the same rigidity and temperature.
If the tank still needs to be cleaned, you need to remove all live fish and plants, to wash, disinfect and dry. After this capacity is filled with new water. In the first few days in the aquarium may be a short-term bacterial outbreak with water turbidity – not to worry, she held herself. Then as the water again becomes clear, in the aquarium you can return the plants and fish it is advisable to start in about a week. Replacement of water is often the most effective means for getting rid of bacteria, but fish is a huge stress, so abuse is not worth it.
How to change the water
To change the water in the aquarium is great or electric vacuum pump. Cope well with this task and siphon, by which the sides and bottom of the aquarium can be easily cleaned from food residues and plaque. That the water is not green, the aquarium should be put away from sunlight and off at night artificial lighting. In addition, you need to periodically remove the excess plants and less to feed the fish so that the water is not polluted by residues of food.
Clean water will also help catfish-antitrus that slide along the aquarium walls and eat the coating on them.
A partial water change in the aquarium should be done every week, changing it to 1/5 of fresh water. In order to keep the water clean and transparent, the aquarium should be run clams and Daphnia. Many aquarium owners try to clean the glass of the tank with snails, but they are not very efficient doing it and also pretty much crap. Problems with water are usually typical for "new" aquariums – subsequently, they begins its own ecosystem, the situation is normalized independently. The main thing – to observe the rules for the care of the aquarium.