http://forum.aqua-fish.net/ A forum devoted to aquarium fish, plants, techniques and fish keeping as a whole. en http://forum.aqua-fish.net/?topic=water-for-discus#1 Hello All, I have a 50 gal. tank and Im preparing the water for Discus. The local tap water comes from a reverse osmosis plant. It has a ph of 7.6 with a 0 dGH and a 0 dKH. and a TDS of 250ppm. I have a home R/O system as well. I filled the aquarium with R/O water to lower the TDS. I added KENT Liquid R/O Right to increase the TDS. The TDS is alraedy 132ppm but both dGH and dKH are still zero. If I'm going to keep adding the KENT R/O Right to increase the GH and KH I'm going to end up with a high TDS again. Also if I increase the KH and I use a PH minus, isn't that going to reduce my KH again. Can anyone help? Thanks. hooper 2010-01-03 http://forum.aqua-fish.net/?topic=water-for-discus#2 the PH may or may not be a true reading with a GH and KH of 0..baking soda could be used to bring it up to 4-5 it will also help with the PH and then see where your TDS end up at Discus Don 2010-01-04 http://forum.aqua-fish.net/?topic=water-for-discus#3 I find those readings very strange as when I set my TDS to 60 ppm with the additives my KH always reads at 4 with a pH of 6.6 mickey 2010-01-04