Tap Water

[Koi-Guy]

I am starting my fish tank of 150 Gallon and was wondering, Once I filled up the tank with tap water. How long should I wait for it to be safe to add fish from Chloride and heavy metals from the tap water?

Thanks,

[Sheri Schmeckpeper]

The metals and salts remain, but chlorine dissipates in a couple or three days; but it partly depends on your weather. We have hot, sunny days here in the AZ desert. We keep 55 gal drums ready and it's free from chlorine in 1 - 2 days.

[Jonathan Kadish NYC AA Chair]

I recommend getting a hose water filter as you will be adding at least 2 gallons new water to the tank every day. This filter will take care of both the chlorine and metals.

[Koi-Guy]

Thanks for the advice.

[Vlad Jovanovic]

Hi Koi-Guy, 

Just wanted to give you a heads up to avoid potential confusion...it's not "Chloride" that you are worried about in tap water, but rather Chlorine.

Chloride is actually beneficial for the fish in a couple of ways and is often added at times on purpose. (Mostly to mitigate the effects of Nitrite poisoning and to stave off Brown Blood Disease).

Chlorine on the other hand will kill fish out right.

BIG difference.

[Koi-Guy]

Thanks Vlad.

Vlad Jovanovic said:

Hi Koi-Guy, 

Just wanted to give you a heads up to avoid potential confusion...it's not "Chloride" that you are worried about in tap water, but rather Chlorine.

Chloride is actually beneficial for the fish in a couple of ways and is often added at times on purpose. (Mostly to mitigate the effects of Nitrite poisoning and to stave off Brown Blood Disease).

Chlorine on the other hand will kill fish out right.

BIG difference.

[TCLynx]

Chlorine will outgas in a few days or less depending on the aeration and sun.

Chloramine is a different story (find out what your water utility uses to disinfect the water) Chloramine will take weeks or more to go away with just aeration though I think UV is supposed to help.  If your city uses chloramine you may need to get a water conditioner or chloramine remover (be sure to get one that is safe for food fish.)

Carbon filters do remove chloramine but most of them are not slow enough to remove all the chloramine, however they can sometimes remove enough to at least make baking bread possible.

Hopefully your tap water isn't heavily laden with heavy metals but a carbon filter should help with that and it would help with chlorine though not as helpful for chloramine.