What's killing my fish?

Unless you have some very specific issues for spawning, or maintaining certain species, your GH is okay. Like pH, it is best not to play with it, causing swings; stability is best.

Just as an FYI for those commenting about wells...remember all wells are not the same. There are many well supplied community water systems, where the water is treated just as in a city system.

The community I live in has a system supplied by 7 wells and supplies treated water. In addition, I have a well on my own property. Aside from chloamine in the system, there is some substantial differences in tests on both water samples.

I'll try to find the site link where you can see water results for most any area of the country and will post it here.
 
Thanks for the info on GH. The hardness stuff is all brand new to me; I've never even thought about it in tanks past. On the site liveaquaria.com, it lists many common community fish as having KH requirements of generally 5-15 (varying with fish). According to my test kit, my KH is 70. This has to be wrong somewhere LOL. Maybe on their scale, my KH is 7? I dunno.

I'm going to sit back and see how long my current fish last. It's only been a few months, so they could still be destined to die soon also. I just wish I knew what to do to prevent this. Maybe I should start buying water from my LFS; it just seems like a waste of money sometimes, y'know?
 
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