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Most Frequently Asked

How often should I change my aquarium water?

Most aquariums should be cleaned every 2 weeks on average. It is easier to combine cleaning and water changes by using a gravel siphon, as this also removes any dirt and waste from the bottom of the tank.


When can I add new fish to my tank?

If you are introducing new fish to a matured aquarium, then there shouldn’t be a problem. However, you should monitor the ammonia and nitrite level for the few days following introduction as a precaution. Also, you should quarantine any new fish for at least 4 days in a separate tank before adding to your main tank. This will help to prevent spreading any diseases.

It is advisable to run a new tank with water only for at least 1 to 2 weeks before adding fish, to allow the filter to build up some beneficial bacteria. It helps to add King British Filter Aid + during this period to help the filter to mature. Fish produce ammonia through respiration, and release it into the water through their urine and across the gills. In a matured aquarium, the filter can remove the ammonia quickly before it causes any problems. However, in a new, un-matured aquarium the ammonia will linger and may build up and cause problems. If fish are added straight away to a new tank then the ammonia they produce can poison them and they may die. Also, once you do start adding fish, they should be added slowly and gradually, not all at once. Spread it out over of a period of weeks by adding two or three fish at a time, to allow the filter to adjust to the larger load of ammonia and nitrite.

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Previous Questions

    Latest Questions: Ask the Experts & FAQs

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    The carbon in the filter removes contaminants and chemicals from the water. Therefore, if it is left it in whilst treating the tank for something, it will remove the treatment and whatever you were trying to treat will continue to be a problem.Once the course of treatment has been completed, carry out a 10% water change and replace your carbon filter. The only treatments in the King British range where removing the carbon filter isn't necessary are King British Filter Aid+ and King British De-Chlorinator.
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  • Do fish grow in relation to the size of the tank?
    This is a common myth and is not true. Some fish will have their growth stunted by being kept in smaller tanks, which can lead to growth deformities. However, most fish will simply outgrow their aquarium in a heightened level of stress, often resulting in decreased life expectancy and/or leaving the owner with the difficult task of re-homing their large fish. Common fish that this happens with include: ✔  Plecs ✔  Clown loaches ✔  Angel fish ✔  Oscars ✔  Red tail catfish
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