a giant bical....as if the regular one isn't big enough
I have a red flush....great plant to start out with(my first plant too)....very hardy and forgiving. hmm....it has been my experience it prefers the following:
soil - damp and loose. wet not wet enough where it sticks together/clumps. makes it easier for the roots to spread out and encourages them to as they forage for water. The plant itself may prefer soil that is a little more wet but anytime you can get it to put more energy into the root system; it will pay off later(more roots=more everything else). I just use 60/40 spaghum peat/perlite but there are probably much better mixes so i wouldn't recommend it but can tell you it does work.
light - 10,000 lumens 6500k t5ho florescent seems to be the sweet spot for lowlanders but the bical can probably handle more. Only reason I do not give it more is I also have a raffesania var elongata and a mirabilis var echinostoma which 10k it closer to the upper end on those for light intensity...little red spots on the leaves but nothing on the bical. guessing 12-15k lumens for optimal artificial light. sunlight is best but not recommended for a terrarium. I say keep giving it light until you see a few sunburn spots on the leaves but less that 50% of the total leaf.
humidity - more the merrier. higher the humidity faster it will grow. i wouldn't go less than 70% for any period of time tho. it seems to prefer 85%
temp - it can handle higher temps but doesn't prefer them however max temp depends on humidity.....more humid it is the more heat you can get away with. Personally mine is 90f for days and 80f for nights but i strongly suspect it would prefer 85d and 75n but it would take me quite a bit of effort to maintain those temps whereas it hardly takes any for the ones I am maintaining now. I have had them up to 105f with no ill effects.
watering - it is forgiving to overwatering but as above water enough to maintain the before-mentioned soil texture. typically very little water daily or more water every few days.....just don't let the soil get dry.
potting - can take repotting but doesn't prefer it...start out with a 4 inch pot and go from there making sure the pot is at least double the leaf span. Usually you can tell how good or poorly you are doing by the amount of roots you have when you repot. Just be warry if it looks like the plant isn't doing much above ground that is because it is doing all it's work below ground
when it is satisfied it has enough roots; it will grow at an explosive rate. provided it is happy and even if it isn't it will still grow quickly.
additional - look into evacuation and/or circulation fans to circulate air....all that humidity will easily breed all kinds of nasties if it isn't at least evacuated. if you have the means to control your environmentals easily i would suggest just finding out what the temps and humidity is in the jungle it came from and use that as a template.
edit: this is for an actual plant...seeds may require more of a wet soil. in conclusion it is very tolerant of a wide range of conditions but will not tolerate lack of humidity or water in the soil so as long as the dirt is damp and the air is humid you should be fine. happy growing. p.s. if you decide to do cuttings later put me on the list