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Congratulations on the purchase of your new aquarium! Now to get started you must complete the following procedures before any new additions of livestock are to be added to your new tank.



All aquariums are recommended to have some form of filtration in the tanks, and we’re not talking about a fancy piece of equipment to keep your water clear. An efficient filtration system should contain at least (in order of filtration) a mechanical stage, chemical and biological, but each tank may be use each for a different application.


Mechanical filtration means all physical matter is collected first.  This is usually done by filter wool or cotton. This is done as a means of trapping fish waste, excess food and anything large enough to be caught up in the weaves. It is a cost effective way to ensure no waste passes through the rest of the stages where it can be trapped, decay and cause your water quality to decline. Ideally these should be changed every 1-3 weeks, depending on stock levels in your tank.


Chemical filtration is anything that will help chemically filter your water. We use filter wool in the first stage to stop the waste from passing by and clogging this stage. In this stage we use carbon as the most common form of media, but there are many different products that can be used in this stage. Carbon helps to polish the water of microscopic molecules in the water. As water passes through the wool that has trapped the large waste, microscopic particles will be bonded to the carbon as it passes through the media. Carbon can help keep your water crystal clear and free from smells but also absorbs dangerous heavy metals, chlorine and choloromines.


Biological filtration is done by using bacteria as a means to remove toxins from the water. Once all the water has passed through the other stages, it now comes down to removing waste water that can only show by water testing. Aquarium water is constantly “CYCLING”(see below). Bacteria is used to break down toxic chemicals that become present in the water from normal fish activity that causes biological waste, such as eating and creating waste. The beneficial bacteria, that is harbored in filter media, feed off these toxic chemicals to make your water safe and toxic-free.


The Chemistry

Now there is some basic water chemistry that you must learn in order to keep your new pets in a healthy environment free from stress and diseases. One thing that you will hear about is the ‘Nitrogen Cycle’ also know as the ‘Cycle’ in which all established tanks will constantly go through. The three main stages of the cycle are Ammonia, Nitrite and Nitrate. Each stage is called ‘Nitrification’, we will go through each stage and how explain how it all works.


When any type of biological matter is present in the tank, it will break in water and create ammonia in the water. Biological matter can be anything ranging from left over food, fish waste, decaying plants, dead bacteria etc. Any of the above will decay in water and create ammonia in the water. Any ammonia present in the tank will be highly toxic to your fishes health and will cause stress and diseases.


Now how do we remove ammonia from the water?

In a well established tank, bacteria is harbored to break down ammonia. In a new tank that has not been established there is no bacteria present to convert this to the next stages.


Nitirite is the next stage of the biological break down. Once bacteria has fed off of the ammonia, the by product that is produced is called Nitrite. These two forms present in any water is highly toxic to any living creature and must not be present in any aquarium before adding any fish. If any of these levels are detected after fish have been added, immediate action must be taken.


Nitrate is the last stage of the cycle. It is the least toxic form of biological waste to your fish in low levels. Freshwater fish are more resilient to nitrate, and have had studies shown fish to tolerate up to 100ppm of nitrate in water, although no studies have shown how the long term exposure of elevated nitrates will effect your fish health. It is highly recommended to keep the levels below the 40ppm. In saltwater systems, ideal levels for fish only systems is under 20ppm and reef systems 10ppm. To keep these levels low and regular maintenance to the tank is required by frequent water changes, removing excess food/waste, changing filter wool and vacuuming the substrate.




How to start the cycle

A proper cycle to build up beneficial bacteria can take up to 3 months to properly establish a tank without any extra additives. With more research and development, establishing a tank can now be done in a much shorter period. Many companies have developed additives to speed up the cycle by adding either live nitrifying bacteria or boosters to increase the rate bacteria reproduces and colonises in a tank.


For all set ups that will started by using tap water, a ‘Water Conditioner’ must be used to remove chemicals that have been added to make tap water safe for human consumption. The main active chemicals in tap water is Chlorine and Chloromine. These are added to kill off any bacteria that may be harmful to humans, these same chemicals will also kill any beneficial bacteria you have built up in the tank. 


Chlorine can be removed by leaving the water standing for 24 hours to a week. Chloromine however cannot be removed with this method and must be removed chemically by adding a water conditioner. This allows water to be added immediately to your tank without killing any bacteria. You must ensure when adding any tap water or when cleaning your tank, no tap water must touch the tank. When cleaning filter media or on the tank you must clean with old tank water or conditioned water. Use products such as API Stress Coat, Seachem Prime, Continuum Fraction to condition your water.


Building up bacteria in your tank takes time and patience. Bacteria boosters and starters are a great way to efficiently speed up the time it takes for your tank to establish a healthy colony to keep your water parameters stable. Products such as API Stress Zyme, Seachem Stability, Continuum Bacter Gen M/F and Dr Tim’s One and Only are great products to speed this process up. By also keeping your water temperature at warmer temperatures can also help bacteria bloom.


Once your new tank has cycled and has established water parameters, it is advised to only add a few fish in at a time and monitor the water conditions by testing. Regular water changes are recommended once any live stock has been added. It is always advised to do at least a 10% water change weekly for ideal water parameters, or 20% in a heavily stocked tank. Continual monitoring of water parameters is advised to have a better understanding of what your fish’s living conditions.

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