getting a reading of 100000000ppm or ppb po4 wont register on a tds meter.. cause a po4 test and a tds test are two entirely different things.davesolo29 link said:[quote author=Duke link=topic=4511.msg42020#msg42020 date=1361666056]
Tds is in ppm.. So getting a reading of 10ppb po4 would read 0 on a tds meter.
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I was under the exact opposite impression.. anything besides pure H20 should give an addition to the TDS levels.. the phosphate checkers simply use whatever means they use to get the Phosphate dissolved solids reading in ppm, ppb or whatever isolated from everything else.. I could be totally wrong tho.