Hi all,

I wonder if you could help me please as my son thinks his cacti are beginning to die and he really loves them.

They have been in his bedroom for about 4 years and nothing I can think of has changed (watering habits same, temp same, etc etc).

Yet, as can be seen from the first pic, they seem to be going brown from the bottom - and the second pic shows that his big one is now going the same way (just moved it downstairs to try and save it) ...

Any clues please? We have some black mould in the shower and on some windows - would this be it??? Room is North facing.

Thanks!
Sword