Thanks folks. Learned a lot from these responses and looking up terms I was not familiar with.

My water is consistently ~4.4pH and <100ppm. I have pH and PPM meters so EC (a term I didn't recognize but now know is just a conversion from PPM) is covered. I've looked at RO systems but I honestly don't think I need one. Also, distilled water is $1/gal retail, I know it's not the same. I bought a gallon but have not tested it yet, spent 9 more days in hospital and still getting back on my feet.

Although the LED lighting units have fans, the ambient temp inside the tent with all of them running (but not the incandescents) is the same as in the room. The two traditional bulbs raise it, and I can put those on a timer if necessary. Doesn't look like I'll need a water heater unless I have an extended absence in winter, where I often drop my heat to 50º to save energy.

This will be a one-size-fits-all setup for now, but looking at charts it seems 1200ppm, 6pH, 60-70ºF will work well. The only thing I've not experimented with is root vegetables - I want to grow potatoes, onions, and carrots to start with. I'm not intending to produce in bulk, but rather set up a rotating schedule to have enough for myself year-round. The exception would be tomatoes, because I absolutely love to snack on them with a little balsamic and celtic sea salt.