The fish don't last?!?

A water softener is built into the home's plumbing system. I know this because I have and use well water that passes through a softener. The softener should have no ill effects on your fish. Bypassing such a system is impossible.

It is definitely not impossible to bypass the system. In fact most installs done professionally, and in some states, required, have a tap and bypass line upstream of the softner. This is specifically for having unsoftened water. In our area, this unsoftened water is piped to all outside taps. No need to treat the water going outside. If he has a tap getting water from the well, before treatment, he can fill a bucket, let it warm overnight, and get his TDS where it needs to be for the neons.
 
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