06-15-2012, 07:16 PM
|
 |
Member
|
|
|
Join Date: May 2006
Location: Lyalta, East of Calgary
Posts: 4,777
|
|
inline ones that measure TDS in and out of the filter usually run for around $40, most LFS sell them as well.
http://www.jlaquatics.com/phpstore/s...t_ID=ro-aftdsi |