How long does Chlorine, Chloramine, and such take to actually damage fish?

[BassetsForBrown]

I generally do water changes directly into the tank, and then I add the water conditioner to remove the unwanted substances. For my 90g tank, this translates to the fish being in unconditioned water for around 10min. They have still seemingly thrived for 2 years under this practice. Does anyone have a study they would be willing to present demonstrating the harm, or lack thereof from this exposure?

I'd like an actual study, but I also would very much welcome opinions based on experience.


Thank you for your help!

 

[cleanpainter]

I wonder the same. I do that in one tank but not the other. I have never noticed ant ill effects.

 

[David R]

Why not add the dechlorinater before adding the new water, just to be on the safe side?

 

[BassetsForBrown]

Why not add the dechlorinater before adding the new water, just to be on the safe side?

because I use a DIY "Python" to do my water changes. It drains the tank until I close the valve, and then I refill it through the same hose. using an intermediary, dechlorinated tank, would mean refilling bucket by bucket.

 

[Oscar Mike]

No need for a separate tank or buckets, just dose with dechlorinator for the full tank volume before refilling. If you're worried about the added expense of using more dechlorinator, a $25 container of seachem safe will treat 200k+ gallons

 

[ryansmith83]

because I use a DIY "Python" to do my water changes. It drains the tank until I close the valve, and then I refill it through the same hose. using an intermediary, dechlorinated tank, would mean refilling bucket by bucket.

I do daily water changes on fry tanks and discus tanks. I drain them to the point that the fish are lying on their sides. You add dechlor directly to the tank before refilling. It will neutralize the chlorine as the tank fills and the dechlor dissipates through the water. Just pour it right into the tank. If you use Safe, which is powdered Prime, you can sprinkle it right in or mix it in a small cup of water and pour it in.

Regardless of the amount of water you are actually changing, the dechlor directions tell you to dose for the entire volume of the tank. If you have a 100 gallon tank, you dose for 100 gallons regardless of whether you change 25% or 90% of the water.

 

[David R]

Not sure why your python would make a difference, instead of; drain tank, refill tank, add dechlorinator, do; drain tank, add dechlorinator, refill tank. Doesn't really matter how you change the water change, just put the dechlorinator in the tank before or while you're filling it.

 

[Libpete]

I drain them to the point that the fish are lying on their sides.

Regardless of the amount of water you are actually changing, the dechlor directions tell you to dose for the entire volume of the tank. If you have a 100 gallon tank, you dose for 100 gallons regardless of whether you change 25% or 90% of the water.

Did I just read that?

 

[tiger15]

Chlorine and chloramine damage is instantaneous, and you know it as the fish will show stress, grasping air and die quickly . There is no residual chronic toxicity effect on the fish if the fish is lucky enough to recover from the chlorine/chloramine toxicity, because it means that all the chlorine/chloramine are gone by aeration or neutralization.

You can add declor to the tank before filling up with new water. You don't need to dosage the entire volume of the tank, just the new water, but I always play safe to put double the recommended dosage to safeguard increased chlorination by water company due to pipe repair work or storm events.

 

[dogofwar]

+1

I just add some de-chlorinator before I refill.

Most fish will die or show real distress right away if there is much residual chlorine or chloramine...

Matt

Chlorine and chloramine damage is instantaneous, and you know it as the fish will show stress, grasping air and die quickly . There is no residual chronic toxicity effect on the fish if the fish is lucky enough to recover from the chlorine/chloramine toxicity, because it means that all the chlorine/chloramine are gone by aeration or neutralization.

You can add declor to the tank before filling up with new water. You don't need to dosage the entire volume of the tank, just the new water, but I always play safe to put double the recommended dosage to safeguard increased chlorination by water company due to pipe repair work or storm events.