Wanna’ hear a joke? What do you get when you cross chlorine with a fish tank? Dead fish!
Whether first starting out w/ a new aquarium or adding water to an existing aquarium, you must add water that contains as close to 0% total chlorine as possible — or your fish will die. For an explanation of the difference between free and total chlorine, please refer to an earlier blog entry entitled “Free, Combined and Total Chlorine Re-Visited“.
It goes without saying that you will want to your the source water for TOTAL chlorine, and not just free chlorine because ALL forms of chlorine can prove fatal to aquatic life even in small amounts.
You may use test strips, liquid test kits and/or a water testing meter. The exact testing method does not matter in so long as you trust the results you get from your testing. Keep in mind that your fishes’ lives depend upon that reading so choose your testing method carefully!