I've moved to a home with a well and have to adapt my aquarium. The hydrologist who tried to explain our lab results characterized our water as "bizarre." Here are the numbers out of the tap: sodium 221 mg/L conductivity 1130 chloride 250 mg/L sulfate 76.6 mg/L hardness, total (as CaCO3) 25.8 mg/L TDS 630 mg/L Alkalinity 28.6 mg/L as CaCO3 pH 9.48 I also tested GH with an API kit and got zero. So, the water is soft, salty -- roughly 0.5 ppt -- and extremely basic. The aquarium advice I've read states that low alkalinity results in low pH; obviously not here. I'm guessing that adding minerals (e.g., Seachem Equilibrium?) would be the first step. After that, what should I do to bring the pH down (and keep it down) to a level that fish would survive? And does anybody have a guess what could be causing the extreme pH? Then there's the sodium chloride to deal with. I'm guessing that guppies, endlers, mollies and some other livebearers would be OK with it. It's borderline brackish, not extreme. The only way I know to reduce saltiness would be to add RO water or use it exclusively. But maybe it makes more sense to just choose tolerant fish and plants.