As MT79 noted, you can test the Safeway RO water yourself and find out if it's good or not. Ammonia, phosphates and nitrates are what I'd be looking for. Just make sure that you test each batch you get. It might test perfect one week, but test bad the next week. All depends when (and if!) they change the filters.
One thing to note... you're doing a LOT of stuff all at once to the tank. Like troubleshooting any system, try to just do one thing at a time and see what happens. Take a guess at what might make the biggest impact and do that, and only that. If you make a bunch of different changes and end up with the results you want, you don't really know what change it was that worked!