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Tap water & fish

• Can I keep my fish in tap water?
• Water companies have a legal obligation to provide wholesome drinking water and the standard of tap water in this country has been increasing year by year and is continually monitored to ensure that the quality of the water is maintained. However, water that is fit for human consumption may not be necessarily suitable for fish who have more specialised requirements.

• Does chlorine harm fish?
• Chlorine is added to tap water to maintain the bacterial quality of the water keeping it free from harmful organisms. Whilst this is not harmful to humans, it is harmful for fish and other aquatic organisms, and it is therefore important that steps are taken to remove chlorine before topping up your aquarium or pond. It is recommended that if tap water is used for fish keeping that the water is pre-treated or left to stand for at least 24hrs before introducing any fish.

• Can I test the nitrate levels in the water for my fish?
• There are a number of commercially available test kits to monitor the levels of nitrates etc. However these are only designed as a guide and are not as accurate as the equipment used in laboratories.
• Fish waste, plant and algal growth, overfeeding and poor filtration all contribute to higher levels of nitrate and lower oxygen levels in the aquarium or pond and this can be toxic to fish. Biological filters and good husbandry will ensure that the levels of nitrates in the water are kept to a minimum and that there is a good supply of oxygen to keep the fish healthy.

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