Hmm, my pond water is very "hard" also, going do far to deposit "scale" on objects left in the water. The fish don't seem to mind. The PH is also around 8.7 or so, not quite 9.0 but close. It seems like your water is coming out of a cave, ancient seabed, or something.
Something else is going on I suspect.
If you wish to drop the PH you will need to add acid, but with water that alkaline, you will need to add a LOT of it. Muriatic acid (HCL) is used in aquariums among other things and can be cheap and available. It is used as wood bleach. You would have to figure out how to administer it to the well water as it comes out of the well, then agitate it with air to mix it up good. I have seen some great agitators here of water cascading through buckets full of holes on the bottom and plastic objects inside of the buckets.
You will need to experiment with water samples vs. amount of acid to use to bring the PH down. You are essentially creating a water conditioner of your own. Get a good aquarium water testing kit and a chunk of time and I think you can pull this off, depending on how much acid is required.
I think the root of your problem is dissolved salts. Your well is producing brackish water. The fish can deal with it, but they need to be conditioned over time with a slow transition from fresh to the higher levels of salt. I believe fresh water becomes "brackish" at 5000mg/L (0.5g/L-30g/L) and you are very close to that.
There is a person here who is raising salt water fish alongside fresh water, someone please remind us who that is? He may be able to help.
Last edited by liquidsquid; 01/04/16 09:38 PM.
