Phrag. fischeri culture at Fox Valley:
1) Intermediate temps; 60F - 80F works best for us. Higher temps to 85F for short periods are ok, but not on a regular basis. Plants won't die, but they won't grow as well
2) Low light, similar to besseae - 1,000- 1,200 fc. Higher light levels tend to bleach leaves. Lower light levels tend to produce larger, more succulent leaves.
3) High quality water (TDS = 40-80 mg/L) and apply frequently. We blend R/O w Chicago water to get within this range. Final pH = 8.3
4) Fertilize very lightly @ 1/8 tsp/gal every fourth watering. We're currently using MSU for R/O.
5) Many of this species tend to self pollinate on almost every flower, so unless you're planning on producing seedlings and are willing to take the risk, cut those seed capsules off before they drain the plant of energy.
The caveat: I have an old saying "What works for you, works for you". If you're currently growing Phrag. besseae and (especially) schlimii well; don't start changing everything in your environment to these values. They work for us and are a good guideline, but they're not absolutes.
Hope this helps.....