I'd recommend beautiful Epiphyllums = Epicactus will be the best choice IMHO. A happy new year!

E grusonii is very tender to sunburn till it established.

True H versicolor looks like fox fur.

First reminds mites second sunburn. Maybe both burned it happened easily ones in the open air.

Many thanks and also want to wish a merry Christmas and a happy new 2024 year to all!

I know many growers use suitable cat litter successfully.

De nada!

It's commercial bunch, trust me.

Hello! Pechycereus pringlei, very simple species. It's brother P. pecten-aboriginum is more warmth-demanding, but this one overwinteren many winters at about 10C with very poor artificial light.
PS Plant them separately, very large/huge plant.

Why didn't you use systemic neonicotinoid x2 to forget all troubles?

1 Mammillaria/Krainzia guelzowiana
2 Mammillaria gracilis Oruga
3 Rhipsalis cereuscula
4 OK
5 Notocactus uebelmannianus
6 Mammillaria marksiana
7 Eriocactus magnificus
8 Mammillaria haageana

Soil mites.

Don't worry. They're very hardy, I've never lost them. If it just broken, heal surfaces with sulfur powder and let dry. Wait and watch, maybe base part hasn't lost it's point of growth and will regrow. Anyway if there're ever one alive areole it will regrow. Top / separated tubercules also wise to p...

Pilosocereus chrysostele IMHO

Maybe dried tissue is too hard for roots to grow through? Cut it (dark dead dry tissue) very tenderly(!) away, maybe you'll find top of the roots there. Did you hold it in vertical position? This spesies is soooo easy.