This is what always happens to my C. Muscosa. I'm not really sure how to get that thing to grow roots and keep them there. Am I watering too much, not enough? Is the soil supposed to retain more water? Less water? I would just take. Those pieces with green at the top and bury them up to the first set of undessicated leaves in a well-draining mix and let it reroot. Just don't let it get soggy. I like to use a spray bottle to root succulents.

It is best to take off as much of old soil as possible - leaving it defeats the purpose of using different mix - at least to some extent. It is recommended to add 'generous amount of perlite, 50% or more' - I think you did well :) You could grow succulents in pure perlite, or pure pumice, or pure grit (or some other inorganics) - they all provide good drainage and aeration. Some bags of perlite have lots of dusty fines, so it may be good idea to sift it. I use a kitchen sieve to do that, putting all sifted perlite into a container with warm water (most likely it doesn't have to be warm, just the way I do it) and rinse it. Then I strain water using same sieve and use it. If I was to use the mix you mentioned, I would sift it too; most often there is still lots of fines in the mix. You should check if there is list of ingredients on the bag to see what it contain. Too much of organic ingredients may attract bugs like fungus gnats since they like wet organics. Not saying you shouldn't use it thou :) Many ppl. use this mix, just have to be careful about watering (that's why addition of perlite-to make drainage better). Personally, I don't buy it since I don't really see any benefit using it for succulents.

Hi, Thank you everyone very much! To answer your questions: - Location: Melbourne, Australia - Sun: this area gets a good half a day of direct sunlight - Water/Drainage: This photo as I mentioned, was taken immediately after it rained, so it looks very wet. It is generally well protected from the rain by the leaves. Yes the rocks and sand and coal (i think perlite is another name) is ⅔ of the pot from the bottom. There are 4 big holes in the bottom of the pot and it drains really well. The plants were growing like crazy in this pot for over a year. And I replanted them 3-4 month ago, adding those rocks and sand. So the drainage issue is unlikely. The roots looked healthy. I could put some more rocks on top to protect it from the rain even more. -Plant type: don't know the name, it certainly looks just like K. luciae pictured above in Crenda's comment. There is a different succulent on the side. The very tall fast growing one. The leaves start to develop these black spots or dried edges and then bubble almost in an acid burn looking manner and die off. Should I trim those effected leaves?

I am not sure what is wrong with them and would hope someone smarter than I will come along and help out. Not sure if it's a disease or growing conditions not right. But I will tell you that these plants need a fast draining potting mix, and commercial cactus and succulent mixes are most often too water retaining. Remember these are succulents, they hold a lot of water in their leaves and suffer if they are overwatered or in soil that holds the water too long or even dries out and resists water. The best practice with succulents is to have a fast draining soil, and when the plants are dry, water until the water comes out the bottom of the pot. If you want to try to save them I would suggest mixing your cactus and succulent mix 50-50 with either perlite or pumice available at nurseries here, not sure what's available for you there. Both pots need to have holes in the bottom so you would want to replace the one without a hole. If you do a repot and notice rotting stems, the plant probably won't make it.