too soft water

I moved about a year ago and I have found the well water in my house to be deadly to fishes. It comes out of the water softener soft enough to hatch out fairy shrimp but most fish or crustaceans die in it within hours. By passing the water softener gives me green water that quickly turns orange and then settles out a think layer of red rust. It smells like rotten eggs and fish die in it as well. What can I add to the soft water to make it hard and restore all the ions water needs. I would like it to be moderately hard. I have calcium chloride on hand but I have heard it also needs magnesium sulfate and potassium at least. What should I add to restore important and major ions and how much, say, per ten gallons?

Another possibility is to add rocks to my trickle filter that would dissolve and add the correct ions, any ideas on what rocks to use?

Edited by Moontanman, 28 March 2009 - 06:39 AM.

Don't run it through a water softener and then add buffers to raise hardness. The water softener works by ion exchange, replacing "hardness" with normal salt. Your fish will feel the resulting water as harder than it previously was since it takes two sodium ions to replace one calcium.

There are a couple options. One is to buy bottled water at the store. That can be prohibitively expensive for large tanks, and it's never convenient. You could do water changes with water collected where you got the fish, if practical. Or you could get a reverse osmosis unit on Ebay. The DI canister that usually comes with them isn't necessary for your purposes, but you can use it if you want. I've heard good things about a product called RO-Right that's designed to reconstitute the water with necessary trace elements.

Also, getting green water that smells like rotten eggs when the softener is on by pass is not good, I have a well with very hard water and high ph, and was getting a little rotten egg smell at times. I was advised to shock my well twice a year, have done so and have no more problems. Water out of a well that kills fish in a matter of hours i would be afraid to consume myself. My advice is to consult a local water treatment expert. Even when my water is a little off in odor or color, it never kills fish....scarey thing to me.

You have bad well water. The water softener eliminates taste, odor and color to make the water palatable to humans. These are considered "secondary contaminants" and are not harmful but are unpleasant.

The water softener exchanges salt for the iron, manganese and hydrogen sulfide you are seeing and smelling. Not good for fish.

Typical water treatment for those contaminants is to oxidize them either with chlorine or potasium permanganate [among others]. Not too useful for fish husbandry though.
If I were designing a fish safe treatment regimen for your water, I would suggest aeration.
Gotta run now but if your interested, PM me for in depth water treatment discussion.

Sombunya works in a water treatment plant too. Where's he when you need him?