Instead of sand use 50% perlite.

tj

It is the nature of this plant, to a more or less degree, to shed lower leaves as it grows in height and makes new leaves at the top.
The rate of loss and the yellowing of the tips on so many of the lower leaves, could indeed be an issue of drainage and watering.
Sand is NOT a good option although it has its uses but in this case a 50% addition will be heavy and compacting down like concrete when dry, being then hard to wet, and allowing little air movement around the roots.
You are far better to stick with a commercial potting mix, which is usually organic and provides not only better drainage but good air circulation around the roots.
Being winter, I am not going to suggest you do anything too severe, you had best wait till the weather is warming a little.
As you have 3 trunks on the plant, I would sacrifice the longest one to try cut off the top and root it, and chop up the rest of it's trunk into pieces a few inches long (plenty of articles on the web about this) to try to propagate more. That way at least you will have some new, lower foliaged plants, available to add to a planting later and provide a bit of coverage for the rest of the trunk. You could do this progressively with the others if you were successful. The cut part of the original plant should also re-sprout side shoots, although all this will be very gradual.
When the weather is warmer, I would remove the plant from the current mix and re-pot it in a better mix. You don't have to wash off all the soil but give it a bit of a shake to remove the excess and then backfill when you've replaced it in its pot, and fill up again to the original level, water and leave to recover.

Thank you so much!!!!! Ill wait for the spring and then replace the sand :)

This post was edited by Mohort on Tue, Jan 27, 15 at 4:16