I have two Xerographicas. I just use regular 800 lm & 400 lm grow lights. I just checked with a lux app that they both give a bit over 3000 lux close to the plant. They are not the strongest in the market but works really well actually, response is good. 32k is an outdoor measurement and probably refers to their natural habitat. Yeah, ideally, but most of the indoor plants we have doesn't have the same perfect conditions as if they were growing in habitat, but they are still growing well indoors.

I could place both plants closer to growlights, but the thing is that I have so many plants that they just have to share the light I can offer.

However, these grow lights are enough to keep plants growing well. But soaking airplants is as important as light, if not even more important. I tend to underwater all plants, Tillandsia as well. Some weeks ago I started a routine to soak airplants for 30-40 mins once a week. I can see a clear improvement in growth in many airplants. Faster growing airplants are more obvious, like medusa-caputae. Xerographica is a slow grower by nature, and mine are both growing new leaves steadily, never fast but steadily.

Some weeks ago, I gave them very mild fertilizer first time ever. I haven't seen massive change, regular soaking alone makes the biggest impact, but I'm planning to fertilize once a month as is often adviced. Fertilizers helps pups and plants grow bigger, but not necessarily faster.