Thank you randy.
We would like to measure the basics, Amonia, nitrites, nitrates, Phosphates, Ca, Mag, Alk.
Most of all is we thougth than if a group puts together the cost, we could have a better readment. But is hard to find the reagens, and some colorimeters do not reag Mag, so we are going to be ending buying mag test. LOL
Thank you guys for all yours aportations.