I have a very tall 'cactus' - from the search I just did online, I believe it is actually a Euphorbia Trigona - that has branches that are becoming infirm and droopy. They looked a bit withered, so I thought it wasn't getting enough water. After giving it a bit more than I usually would for some weeks now, it seems to developing more droopy branches. I've grown this plant since it was ~10" tall. It is now at least 5' tall. I would cry if I failed to save it from whatever is going on. Am I watering it too much? I was just doing what I always have done before it started drooping..... It has not turned color, still a strong green. No browning or anything. It otherwise seems okay... Can you help??
Sounds like root rot. If it is I'd take insurance cuttings and pot them in NEW cactus potting mix, in NEW pots.
