jonny_ftm;36988 said:Do you really think that the few Cl2 you'll add could hard your plants? CaSO4 is just cheap compared to CaCl2, that's why for sure they use it rather than CaCl2
Philosophos;37103 said:4ppm Cl tap water does ugly things to fish. I've seen plants do fine at this level, but I don't know of many people who completely neglect to add fauna.
Jose-Miguel;37101 said:Philosophos: you're right with the proportions. Usually Cl2 evaporates from water, so doesn't stay for longer (opposite to Sulfur), but clearly looks as a high ppm concentration.
I don't know in the US, but here in EU the level of Cl is usually higher than 3 ppm. I don't mind this is good, but 3 ppm sounds very low to me.