IMHO it'll be good to include potassium bicarbonate, sodium bicarbonate and calcium carbonate. Last one you already have available for Ca and GH calculations, so KH option can be added as well. Potassium bicarbonate should probably be available for calculations not only for KH but for K as well - it adds quite a lot!
I will be adding several soon.
Calcium Carbonate (CaCO3)
Potassium Bicabonate (KHCO3)
Sodium Bicarbonate (NaHCO3) aka Baking soda
As for bugs, the latest feature, nutrient accumulation calculation, is not yet working properly in some scenarios (e.g. try dose frequency 7 - once a week, and WC frequency also 7 - results are really odd). It looks like as if water change and addition of fertilizers are happening on the same day then calculator assumes that water change will always happen after addition of fertilizers. I guess some people may do this (some of the people who do daily dosing) but IMHO more common scenario is to first change the water and add fertilizers after finishing with water change (or have new batch of fertilizers mixed into water used for change). At least this is definitely more common if WC and dosing schedule is the same - what is the point of dosing the water you are going to throw away? May be this should be an additional checkbox (WC before dosing or WC after dosing if they happen on the same day)?
Fixed. You can now select to dose before, after or not at all on water change days. Setting the water change and dose frequency the same displays correctly now.
There are also minor layout glitches if font in Windows is set to bigger size (125%, 150%) - this is very common on laptops with small high resolution screens: right part of the main window is cut off (unless program window size is manually increased), "About" dialog content doesn't fit and gets scroll bars.
I added a scaling routine that should fix this issue. If not send me a PM and we can track it down.
Auto update doesn't work even if run as administrator.
Update should work fine now. You still may need to run as administrator though.