I'm no expert - but my experience is that cacti are pretty forgiving in terms of pruning. For aesthetics, it is generally suggested that you cut a pad off at the place it joins with the main plant. Altho I have had luck with pads that were sliced right down the middle (I do live in Arizona, so I have a climate advantage over you!) In your case, there are two joints - one way down at the bottom and the other up at the new pad. However, I agree with xerophyte that you should cut off the portion with the new bud - maybe several inches below the new bud - slice through cleanly with a very sharp, clean knife and allow the pad to callus over. You want it to be completely dry before replanting in a loose, gritty mix. Don't water for a few weeks after planting (that's what I do, but I usually put mine in the ground) You could also cut the remainder of that long piece off at the low joint and see if you have any luck getting that to grow as well. I'll bet that the main stem will put out another bud. The biggest issue you have is going to be with light and, maybe, heat. If your cactus does not get enough of either, it will continue to grow long, goofy-looking pads. But I encourage you to try pruning that top bit off and see what happens - it can't hurt! :-)

As was stated, remove all that new growth. Keep in the brightest light possible. Also, be careful of those little spines, called glochids. They easily enter the skin, and are very difficult to remove. Christopher

Yes, even considering the angle of the shot, they are waaay too low. The soil level should be about 3/4" from the rim of the pot. When they are low like that, the edge of the pot blocks light and air circulation, keeps their environment too humid. If you look at pictures on other threads of people who are experienced with C/S, you can get an idea of how high to pot. The soil may have been too compacted over the 2 years you have had them. It also looks fairly wet. As for the collapsed one, it looks pretty bad. If you want to pursue it here, take a picture and post after you remove it. If it were taller you might cut off the bad, let the green harden off, and then pot it. But it looks like it's pretty much dead. You should be able to save the other two. Good luck. We'd love to see how you repot them if you feel like taking another picture. By the way, I probably don't need to tell you the pots need holes in the bottom.

Hi guys again I have to ask what is going on with one of my cactuses It has been doing it for a while and I had it for 3 years now Please help me know what it is it doesn't seem like a root rot Only the tops are a little loose and are doing this