Amit asked, "I won't use the CO2, My tap water already comes with PH of 7.2 and KH of 10 - does this eliminated my need for a CO2 system ??? Do plants do better in a KH between 3-8 ?" First, it is true that tapwater right out of the pipe can have extra dissolved CO2. To get a more accurate reading of your water's characteristics, let it stand in a glass for a day and then check its pH. But let's assume that your tapwater has perfect CO2 levels. You put it in the tank. The plants us the CO2 which is in the water. They use it up - pretty quickly, if they are growing well. Where do they get more, unless you are constantly adding either new, CO2 rich water from the tap or or CO2 from some other source? Second, according to Tom Barr, most plants aren't that sensitive to GH/KH, and 10 should be fine. Hope this helps. -rs --- StripMime Report -- processed MIME parts --- multipart/alternative text/plain (text body -- kept) text/html --- ------------------ To unsubscribe from this list, please send mail to majordomo@thekrib.com with "Unsubscribe aga-member" in the body of the message. Archives of this list can be found at http://lists.thekrib.com/aga-member/