Sherry Michael Weller wrote:

I have found myself in the posession of a small DI unit. I know a bit
about DI water and I'm really excited to use it to process my 'liquid
rock' tap water.

I know that they sell additives to replace trace minerals and salts to
DI water. Can I simply mix DI water and tap to get the right GH?

Yes, this works fine.

I'm worried that the wrong PH buffers in any of these additives may
increase
algae blooms.

Using buffers to adjust pH is seldom good solution.


I know you can't measure the pH of DI water. My goal is to try to get
soft and slightly acidic water (peat treating if neccessary). If I mix
DI and tap, can I check the PH?

Yes. pH tests fail when chemical buffers have been added. Since you are
wisely avoiding that path, you should be fine.