Learning about ph... concreat tanks... and RH

[gary harding]

I am just now starting to dive into the aquaponic design and operation of my system, finding out about ph and concrete tanks. Here is an interesting site that enplanes  RH and PH in rain water  here in the USA.

  http://www.wagnermeters.com/ph-same-price-as-rh.php 

I am starting to understand that i need to line my tanks with a liner, check ph in water supply(well water) and check ph in fish tanks. Rain water collection will be lower ph below 7.

[Vlad Jovanovic]

Yes, line or otherwise seal your concrete tanks (wax or fish safe epoxy) because the limestone contained therein will forever be raising your pH. Some have claimed that a one time acid wash will do the trick,but check into that one yourself, find out how that method pans out long-term...Some sort of sealant, barrier, liner seems safer.  

pH (and hence acid/base reactions) is (one of the) the single most important parameters to grasp for successfully doing AP. Good luck.