Ok i got a 5 gallon tank and i added dwarf hairgrass. Substrate is fluval plant stratum i use co2 and fertz. My light is a 13 watt 5000k compact florecent bulb. Is the lighting enough to keep my hair grass to grow and prosper?
Sometimes you can get a good desk lamp. But you would have to take off the lid, so you would have a lidless tank. Or I know walmart sells fluorescent bulbs for your tank at the aquarium section. Its brighter than the stock ones, and better than walmarts plant growth bulbs. I do get algae after leaving it on too long though.
65k is probably better but since it's 5gallons(not too deep) I think you should be ok. I would say see how things go for a week or two and trim it to promote more growth and if you don't see any new runners I suppose lighting upgrade might be worth trying.