Setting up new tank

[oasis]

ro water is not the same like aged tap water, there are still more bad parts inside the water , a reversed osmose system takes out the bad parts , the product what you put just nutrelise the cholrine in the water, and binds the heavy metals together, but they stay in your water. therefore the ppm (parts per million) is mutch higher then in ro water.there they are filtered out and you have something like 20 ppm, tap water is like 250 - 300 ppm or even higher, depends the quality of the water

Thanks for the explanation. But any reason the brown algae suddenly disappeared? The Ph in my tank is about 6.0 after 1 week of cycling without live stock