just another nano

[dw1305]

Hi all,

Hi, just took a TDS reading this morning, came out at 110ppm. last night i done a 30% water change with the tap water coming out at 339ppm. i have only used tap water in this tank, so it got me asking, "did the akadama lower the tds?" just some food for thought.

Yes, it will do at first. The reason is that the cation exchange sites are initially filled with H+ ions, which are exchanged for Ca2+ etc ions.

The TDS meter is actually measuring conductivity (and then multiplying by a conversion factor - somewhere in between 0.5 - 0.65) to give a ppm TDS reading. H+ ions don't conduct electricity, but metal ions do.

A fuller explanation is in the "Akadama" thread <http://www.ukaps.org/forum/viewtopic.php?f=17&t=741&p=175752&hilit=low+base+saturation#p175752>.

cheers Darrel

 

[logi-cat]

thanks for the link.