[oldsaint]

I do a 25% water change every week. Usually after the 3rd one I test for iodine, strontium, magnesium and add if necessary. The iodine and strontium test are a real pita so sometimes I let that slide into the next water change but I normally get to them at least once a month.
Other than that, I dose calcium hydroxide, 8 tsp per day added to my topoff water and B-ionic 1 & 2, 1/4 cup each early in the morning before the lights come on.
All product are ESV except I use Lugol's solution for the iodine.