Although having a good filtering system will ensure that solid waste are removed, however these doesn’t work for those soluble chemicals that dissolve in water. Therefore, regular partial water change is a must if you intend to ensure that your fish stays healthy.
One of the myths surrounding new aquarium owners is that, if you notice that your aquarium water level is reduced, merely replacing the evaporated water is not sufficient to overcome water chemistry changes. This is because the dissolved chemical still remains inside and thus, you are merely adding fresh water to dilute it. Therefore correct way of aquarium maintenance is to remove wastewater first before you add in fresh one.
So the question now, is how much to change the water and how regular to do it? Based on my own experience which are shared by the most experienced hobbyist, the best way is to remove one third of the aquarium water once a week and replace with fresh water back to the same level. This is based on the assumption that your aquarium is in a healthy balanced state. However, there are factors, which may alter the frequency and amount of water to take out. Listed are some of it:
- Stocking Density: An overstocked aquarium will require shorter intervals of water change in between
- Age of aquarium: Water chemistry in newly startup aquarium will generally need more water changes in order to maintain balanced state. This is because, it takes time to establish the colony of beneficial aquarium bacteria that breaks down ammonia waste. Therefore, check all the water parameters like pH, ammonia and dissolved oxygen during this critical period.
- Types of fish: Larger fish and those that produce a lot of waste like goldfish would require shorter intervals of water change. On the other hand, smaller fish like neon fish would thus require less water maintenance.
What is Nitrogen Cycle?