It is "not" true the chloramine will dissipate after sitting, the way straight chlorine does.
At our water quality lab, we put a gallon on chloramine treated water on a shelf, and tested daily for residual. Even after 2 weeks, the chloramine concentration barely changed.
The organic content of water in many aquariums, is enough to neutralize a large part of the residual in tap water though. And some of the residual chlorine in tap water can be very low depending on the source. Where I lived chloramine came out of the tap at 1ppm or less because of our source water.
You can call your water company to get an average dosage, or get test strips from a pool supply store, or even somewhere like Home Depot for test strips to be sure.
Just because one person has had success with neutralizing Cl2 in their tap, doesn't mean someone else will.
At our water quality lab, we put a gallon on chloramine treated water on a shelf, and tested daily for residual. Even after 2 weeks, the chloramine concentration barely changed.
The organic content of water in many aquariums, is enough to neutralize a large part of the residual in tap water though. And some of the residual chlorine in tap water can be very low depending on the source. Where I lived chloramine came out of the tap at 1ppm or less because of our source water.
You can call your water company to get an average dosage, or get test strips from a pool supply store, or even somewhere like Home Depot for test strips to be sure.
Just because one person has had success with neutralizing Cl2 in their tap, doesn't mean someone else will.