This came up in another thread but if you want to be really careful, it's best to test the tap water for chlorine levels before you do a water change. There are chlorine tests but someone suggested pool test kits are close enough.
You can then dose accurately.
The main reason to do this is so you'll know if the water company dosed extra chlorine or chloramine. There have been threads on here where people have lost fish because of this happening. Water companies might do this for maintenance reasons or because a storm. It's not at levels that are harmful to humsan but they could kill fish.
These 50 strip kits are like $7-9 on amazon.
I usually do it when I water change my 125g because there are more fish there and I have my 21+ old clown loaches and pleco in there. I often just risk it with the QT tank because the chances of it happening are slim anyway.
I also just water changed my main without using the test strip as I changed the QT water a few hours ago and no fish died there so I just assumed it was normal chlorine levels.
Correction:
These are now on Amazon for $6.41 so that's 12.8 cents a strip. Cheap insurance on the off chance something happens in the water.
Also I should add less safe. My report shows 1ppm but I consistently get 0.5 from these strips.
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