On Apr 10, 7:12�pm, parakeet
wrote:
[image:http://img397.imageshack.us/img397/4...bd2455xt3.jpg]

This cactus used to look entirely different a week ago. A lot chunkier
and healthier.

I've been noticing tiny flies around my house for some weeks (upstairs,
downstairs). I figured it may be related to a dodgy spider plant
elsewhere in the house.

But I noticed today that the tip had shrivelled up. On closer
inspection, I saw that the flies were congregating on around the cactus
(tapping it revealed a couple more).

Also of concern - prodding the cactus reveals it to be rather flimsy;
feels hollowed out inside somewhat.

Is there any way to turn this around?! I'm beside myself, because I
inherited this from a late friend.

On my father's advice, I filled a squirty bottle with water and some
washing up liquid and sprayed the plant with that. In his experience,
that's killed blackfly on leaves.

That soil doesn't look right for cactus, should be more sandy. You
may have over watered it. I would slice off that top portion and get
rid of it, it looks diseased. If with a sharp pen knife you pare out
one of those nodules, coat wit a little rootone, and plant it you can
make a new plant.