Water Experts Needed

[br1dge]

Considering a Planted discus.. Tap water is very soft, but otherwise rather odd (to me anyway)

From the tap

TDS 40ppm
ph 7.7 / 7.8 (Measured with a calibrated Milwaukee Meter)
KH 1.75 (averaged over several tests using AP reagent test kit)
GH 2.55 (averaged over several tests using AP reagent test kit)

So crazy soft, I know, but why the high PH? I thought the softer (more pure) the closer to neutral.. Still learning all the relationships. Any ideas?

 

[Watcher74]

Kh is often an indicator of pH but really isn't. Kh is alkaline, but if some sort of acidic presence is around to counteract it then it would drop the pH but not affect the Kh. Acidic elements do not remove alkaline elements, only counteract the pH affecting qualities that Kh provides.

I would describe it as two kids on a see-saw. First only Kid A (Alkaline) is sitting on one end. Say he weighs 90 pounds. So the other side of the see-saw is high(like a high pH). Then an 85 pound kid B (Acidic) jumps on the other end and drops the level of that side to just a little higher than neutral (7.0).

Kid B did not make kid A dissapear or lose 85 pounds, leaving him weighing in at only 5 pounds. He only counteracted his affect on the height of the other side of the see-saw because he added his weight to it. (Does this make sense or am I just a nut?)

There are other things beside Kh(carbonates and bicarbonates) that can raise pH. Hopefully someone else more knowledgeable will chime in. Because I only understand what I have stated and little more.