Hi, I'm a bit confused; I bought two Majesty Palms a little over a year ago when they were 4' and 5' tall; they barely fit in the car with the sun roof open. I repotted them a few days later and they have been in my living room since. They receive no direct sun light and have plants lights on for about 8 hours a day. I water them with 2 quarts purified water with Miracle Grow added as directed for weekly watering. My problem if you can call it that is they are growing like weeds! One is now over 7' tall (it has 3 fronds that height and two more growing) and the other is just going on 6' (its newest frond will be that height with 3 more fronds in progress.) Luckily I do have 14' ceilings so I am happy to let them continue to grow, but I want them to slow down a little. I read that these trees can grow to 35' tall and although this was an old hospital converted to condos, a jungle wasn't what I had in mind. Can they be pruned back without damaging the plant? They have no bugs, pests, or diseases, I check and treat all my plants promptly; humidity and temperature seem to be right, what should I do to slow them down?