To add to KoOG' input.
The leaf tip might be a fertilizer issue but it may not be too. I find most Phrags tend to do this over time and the oldest leaves will eventually turn brown and you can either trim them off or if you wait long enough you can just pull them off with a gentle tug. It's a neatness issue only. They are doing no harm.
Your plant looks healthy so I'd say you are making it happy so don't mess with it.
Longifolium is what I call a spreader. That is it tends toward sending out new growths that grow on the same plane as the crown. Schlimii, on the other hand, has a penchant for climbing, that is, the new growths tend to emerge higher up the stem of the mother plant and after successive generations may be completely out of the pot. Not as bad as some Phrags such as besseae but they'll lean that way as their preference. As a matter of fact, the in situ pics that KoOG linked of schlimii show that if you look closely.
And if you want to see what schlimii really loves, check out this thread.
Phrag. schlimii