Use as much light as you can. I put tons of light on my tanks (over 200 watts on each Nep tank) and I also either use tinfoil on all glass tanks or if I'm building the growing chamber I use glossy white fiberglass shower wall so that no light is lost and is all reflected within the enclosure. light light light!
With a lot of light you MUST ensure high humidity of 80% or higher day and night or you will burn the plants and of course, with low humidity it will not pitcher either, the lack of pitchers means either too low of light or too low humidity.
Here's some things I've noticed:
If your plant closes it's pitcher lid and/or reddish brown spots/areas appear and start to "eat away" at the plant's leaves the light is bright but there is not enough humdity. The red color from burning is very different than red pigment caused by bright light & adequate humidity-which is a desireable sort of "burning" as it causes very large pitchers and sturdy/healthy leaves along with visible nectar production but for "positive burn" you must have contsant high humdity.
If you have a plant growing with no leaf burn but no pitchers your light is likely to be too low in intensity. I'd say don't venture into Neps without using at least 4x 40 watt flourescents (160 watts). Six is even better (240 watts)!
It's also a good idea to stop by a Petsmart or Petco and pick up a pair of humidity & temp gages (called a Hygrometer & Thermometer) for reptile enclosures. The ones made by ZooMed are the most accurate (about $12.99 for the pair in one packet) when I checked it against a digital Hygro/Thermo unit I got at Walmart ($24.99). The cheaper ones (some other brand I bought was only $2.99 for the hygrometer) did not record accurate humidty. It constantly measured at a little over 1/2 what the others did even with repeated calibration.
If you're growing in an empty fishtank use a all glass or all plastic lid so you can put the maximum amount of light over the tank. You can cut a few pieces of PVC piping and lay it across the bottom of your tank and place a sheet of eggcrate lighting diffuser grid (from home depot by the Flourescent fixtures in the lighting Dept). you can make a "false bottom" and water your plant inside the terrarium without taking it out. The water which draibns from the pot and collects under the grid (that the nep pot sits on) will create a constant level of very high humdity due to evaporation and condensation as the lights come on and go off for the night.
That brings up a lighting timer.... Automating your lights to go on/off at a set time everyday is nice because the plants get a set amount of light per day and they will easily adapt to this if a regular photoperiod is used. Lighting timers are about $5.99 at any store which sells power cords, extension cords, power strips, lamps, etc.
Make sure when you water you only use Reverse Osmosis filtered water or Distilled water from the grocery store. It must say either of those things and NOT: Mineral Water (R/O & Distilled have almost no minerals and zero sodium), Charcoal Filtered Water, Drinking Water or Nursery Water. Also don't water with cold water. I sit my gallon jugs ontop of my refrigerator overnight so they are nice and warm 70-80*F when I want to do my watering. Cold water will shock their roots and may cause growing problems. I water at least once a week in winter (usually twice) and more often in summer.
When you ware watering do not use a misting sprayer. the fine droplets that land on the leaves can leave unsightly "bad" burn marks on the leaves of otherwise excellent looking plants. Water at the soil not over the whole plant. I use a turkeybaster. When I do a heavy "pot flush" I use a fine holed rose type watering can which makes soft rain droplets and works great for this. After I replace the plants from using this I cover the lid with a distowel to dampen the light until the next day. this usally gives the plants time to absorb the water on the leaves or for it to evaporate. the next day I take the towel off the glass lid and the plants get their full allotment of "sun" again.
Whew. I'm sure I forgot a lot that I wanted to add...!
Good luck!