I don't test anything! London tap water with the chlorine removed so just a tad softer than concrete. Last time I checked PH more than a year ago It came out at 7.8 on a test strip but no idea how reliable that was.
I used to test all sorts of things but no longer bother. I used to try and soften the water and lower it's PH with a buffer for my apisto's, but slowly weened them from it and they still bred. I pump CO2 in to this so it probably drops in PH through the day (I have no idea how much by) Silver tips do fine in it (they are tank bred from eastern europe). I've even given up using a drop checker for the CO2, just never touch the dial and check the bubble count every day I'm in. The plants soon tell you if there's not enough, and the fish even sooner if there's too much.
I used to test all sorts of things but no longer bother. I used to try and soften the water and lower it's PH with a buffer for my apisto's, but slowly weened them from it and they still bred. I pump CO2 in to this so it probably drops in PH through the day (I have no idea how much by) Silver tips do fine in it (they are tank bred from eastern europe). I've even given up using a drop checker for the CO2, just never touch the dial and check the bubble count every day I'm in. The plants soon tell you if there's not enough, and the fish even sooner if there's too much.