I have a good size 3ft tall x 2. 5ft indoor pencil cactus given to me a few years ago. It has been healthy and growing - loves the sunny location I've had it at for 2 yrs. Scenario, the top smaller branches started to get soft and parts were a bit droopy. I have inspected closely, thought perhaps some tan crusty spots/lines were scale? (1/16 inch wide - inch long) I did a complete careful treating with alchohol and Q-tips but then cut off a few and they were not oozing sap. . so cut off a few more, and some DID ooze sap. A few dead pieces, . . so I pruned it very moderatly; took off the branches instead of treating them. Then two weeks later, (getting more concerned) I decided it was time to repot anyway (3+yrs in same soil) . . . and only way to inspect for root rot. I found healthy off white hard roots. . . I repotted in combo Cactus/Reg miracle grow soil. . (mostly cactus) and did not water for a few days. Then moderately watered. I see zero improvement in 2 weeks. . I am torn about this as; my friend who gave me this plant insists that it needs more water than I told her I give it. (No online resources say it needs lots of watering) I watered it religiously every 7-10 days lightly, , less in winter, . . and twice in summer it went outside and got a full flush. (I do not leave it outside - have LOTS of indoor plants must be careful about bringing in pests) Use organic products mostly. Fertilized 3 times a year. Room has skylights and a window near the top edges of the plant. IT is on a table next to this near ceiling flip out window. It got really cold about 60 days ago when I forgot to crank it shut; got to 30 outside. So, . could one cold night by a slightly open window damage it this much? Am I watering too little, ? 2. 5 ish cups at the most every week. Is in a 12 in pot - base stem is solid 1. 75 in. in diameter) 3ft tall now pruned. Major branches are quarter in. diameter. This is bumming me out can't find a thing online to help me know what is causing this soft limpy branch thing. . . HELP! I want to be patient, but if there is something anyone sees as to try. .