Your primary problem is the moisture control potting soil. Not only is it peat based, which is really ill-advised for cacti and succulents, but it is amended with moisture retaining polymers that defeat the purpose of the fast draining soil these plants prefer. Find a decent unamended cacti and succulent mix and then add by 50% volume more perlite, pumice or grit. Sand, unless very coarsely textured, is not helpful nor are larger river rocks. What you should be aiming for is a heavily mineral based potting media with all the ingredients of approximately the same particle size.

@gardengal48 (PNW Z8/9), I did follow the most popular recipe for succulent potting soil that I could find and most of my succulents are doing really well in it.

But I’ll look into what you’ve suggested! Anything to keep these expensive little guys alive, haha.

Did you find that recipe here? I would be surprised if you did........... Ill-advised potting media is the primary comment observed on this forum as to why plants are struggling.

@gardengal48 (PNW Z8/9)

No, it was long before I found this website, haha!

it was from several popular succulent blogs.

I have thought about just buying Bonsai Jack soil (I’ve found that recently as well) but it’s a little pricey.

Thanks for the advice!

Moisture-control soil generally means that the soil HOLDS MOISTURE. GardenGal is correct in her analysis and advice. If you plan to use any regular potting soil or "moisture control" soil -- my advice would be to add so the final mixture is about 1/3 perlite, 1/3 soil and 1/3 washed chicken grit. If you live near a Tractor Supply store, you can buy Manna Pro poultry grit pretty cheap. Needs to be washed but, it's great stuff.