I don't like letting any of my plants go completely dry between waterings (during the growing season) if I can help it. They may tolerate it but they will not grow their best if they think a severe drought is upon them every week. The rainfall totals and the amount of water the plants get in the wil...

It is an Aloe, not a cactus. Can't really do any better than that unless you have pictures of the plant.

1 & 4 are Haworthias
3 Sedum morganianum
5 Aloe, probably Aloe marlothii
7. A stapeliad. Probably a Huernia. You need open flowers to identify them, so get a good picture and post it in a few days when it opens.

Inflorescence would be the more accurate term for these structures. The flowers are the tiny dots.

First one is Graptopetalum bellum (also called Tacitus bellus). Second one will need to grow out more for me to ID it (though someone else might know it now). Third is Anacampseros rufescens. That one needs more light, as you can see by how stretched and green it it. My guess is that they all need m...

The bottom one looks like Rebutia pygmaea

I was in Las Vegas the last few days and stopped in at a C&S nursery with several plants labeled "Aloe aculeata" that looked quite a bit like your plant. Check that name and see what you think.

I believe that is Mammillaria dioica.

It looks like an Aloe but I'm not sure of the species.

I saw something like Delosperma, in California. Instead of grass, everywhere. https://farm8.staticflickr.com/7290/10382597164_aec59d6306_b.jpg https://farm4.staticflickr.com/3712/10382629396_7746cf2e9a_b.jpg Like Ian says, it is Carpobrotus. It is a terrible weed in coastal areas of California. It ...

I've got a Sansevieria cutting that was given to me 2 years ago that still hasn't rooted. The leaf tips have dried up but otherwise the plant seems fine!

Actually I think Hylocereus does it less often. I misspoke in my last post as I meant Harrisia jusbertii when I said Hylocereus.

The rootstock should grow easily. One of the main downsides of grafted plants is that you have to regularly cut off new shoots that the rootstock is trying to make. On Hylocereus I'd say it is at least one per month per plant in the growing season. So in this case the new shoots will be a plus. If y...

You have a Euphorbia, not a cactus, but the care is pretty similar. From what I can see and the fact that you are saying it is getting worse every day, I think it is rotting from the base up. You can still save it. Cut the top off and check the stem (of the upper part, the base is dead) if it has an...

Ian gave good advice. I just wanted to add that while the leaves won't heal any more than it already has, the overall plant will effectively heal in time as new leaves are produced and these old ones wither away. Even by the end of the summer it will look a lot better most likely. I mention this to ...