Micheal,
What's PE??
As for testing for Mg and adding supplements, it's a good idea. You've spent how much on your tank and you're balking at $40 for a measly test kit
1350 ppm of Mg is what to aim for, but I often have it a bit higher, say up to 1400 ppm with no ill effects that I'm aware of.
As a matter of fact, I'm going to do water testing right away this morning. Will be testing for Alk, Ca and Mg. I've got to figure out why my pH has been so high lately
