My tap water is 8.8 and I would like to lower it without an RO System or Leaching Tannins. Any way?
There's no point playing with the Ph value. It has no effect on fish well being on its own. If you want your water softer, you need to use RO. There's no other way. Then again, the Ph value you arrive at via RO water has no bearing on the fish well being. Its the actual mineral content, or the reduction of it, that plays a role for soft water species. So altering the Ph without altering the mineral content is completely pointless.
CO2 reduces the Ph as it affects the ratio of positive to negative hydrogen ions, which is basically what the Ph measures, but it has no effect on the mineral content at all....Except for moving the Ph down, it does not alter any other water specification. Hence fish don't care about Ph move driven by CO2. However, they do care about high levels of CO2 in the water. Some species are not well equipped to deal with that.
That is unfortunate, I would recommend checking out some African dwarf cichlids like kribensis.My RO system both broke because my PH was too high and I didn't want to replace filters after a week. I want to keep German rams and SA Plecos, but my water is too hard.