New Water Smell

Have you used a dechlorinator? You need to use one every time you add water, and if you've cleaned the tank with a source of chlorine (bleach, bottle steriliser etc) it is wise to do a final rinse with water overdosed with dechlorinator.

Water companies add chlorine or chloramine to kill bacteria in the water supply to make it safe for us to drink. They will also kill the bacteria we need to grow in the filter and will irritate fishes' gills. So we add something called a dechlorinator, also known as water conditioner. That removes the chlorine. The first time the tank is fillled, enough is added to treat the whole volume of the tank. After that when we do water changes, we add enough to treat the amount of water we are putting into the tank which is usually about a quarter of the total tank volume.

If your water company uses chlorine rather than chloramine, that will gas off over a couple of days. But it does mean leaving buckets of water standing around the house for a couple of days before a water change - it is much easier to add dechlorinator. Chloramine does not gas off, and if your water company uses this you do need to use a dechlorinator.



Have you read up on fishless cycling before you get fish? It may mean you can't have fish for a month or two but it is much easier than all the water changes you'll have to do if you get fish straight away.

The overdose is for rinsing the tank before filling up. I generally use a bit of water dosed at 5 times what the bottle says. Then when the tank is filled any left clinging to the glass gets diluted.
But if you've already filled the tank, that will mean emptying it again which is a lot of work. I would just add the recommended dose. You'll have the chlorine that was in the water you filled the tank with plus any left over from the cleaning. A lot will have gassed off by now, so just using the dose for the volume of the tank will be fine. As a general rule, it is safe to add 1.5 times the dose on the bottle but no more.




Tip for when you are cycled, have fish and are doing weekly water changes - if the dechlorinator says to add a capful to a certain volume of water you may find it easier to dose the new water using a pipette or syringe. I use babies medicine dosing syringes from the chemist.