theres chemicals, certain substrates will alter PH, i think if you put peat in your filter it will lower it but that might be B.S. i cant remember. what is your ph anyway. i think mines a little high, but the fish seem happy
my tester only goes up to 8.4 so it could be even higher than that, fish seem to be doing ok but I heard this isn't good for them. In the past couple of weeks I've added new driftwood & 2 rocks, they were soaked & scubed. My 2 other tanks test at 6.8 & 7.0. ???
If KH is low, it's easy to get a lower pH with CO2. You can also use turf: cook the turf and use that brown water (but this will color your water). I have heard that bogwood also will lower your pH.
My well water is natually high. But most of the fish I am buying now like it higher and show more color becuase of it. Before I was working against my water. example: I had tetras who LOST their color when I brought them home. To find out they prefer soft water.
Luke Skywalker....don't work against the force. Feel the force.
i use seachem acid buffer to lower the ph for my discus, i usually only need to use it to lower the ph on the tap water before i do a water change, it is a planted tank and the ph stays pretty stable at 6
I'd bet the rocks are the reason it's high. Calcium leaches out raising the pH. CO2 is one of the easier ways to lower pH assuming all else is in check.
I'm fighting a pH battle right now as well with my big tank. It's above 8.8 even after being shocked. I've hit it with a few pounds of sodium bisulfate (powder version of muriatic acid) as much as I could and was going to turn to CO2 to help it down....but I did the math and not even CO2 will get it where I need it and still be safe for fish. I may end up tearing it all down and starting fresh (building it correctly this time).
Thank goodness I don't have fish in there yet.