I will continue to experiment.
I slightly remember ph from grade 10 chemistry but need some more practice. I was into other chemicals at that age...

By the time I get this thing balanced it will be time to change the res...

thanks for the sodium tip.

now further on ph levels, if I am adding up or down to my res and the bubbler is on, does the additive actually mix well with the whole solution? Or, does it merely "float" on the top of the water and evaporate quickly?

so in taking a ph reading, I am only reading the top portion of the solution and not getting an accurate reading.

should I be stirring and take a reading 5 minutes later?