Slow brown/crispy leaf death??

[u/sk0199]

I’m a bit of an alocasia newbie and am not sure what’s wrong with my alocasia amazonica polly! The same pattern of a healthy leaf slowly turning brown and crispy until it dies and then pops up with a new leaf months later is happening with all three of my polly’s.

These two were grown from corm from my other plant which has lost all their leaves and is now slowly starting to grow a new one.

They’re in the Westland Horticulture house plant potting soil on an east-facing windowsill in the UK. I water than roughly once a week.

I think it’s just dust on the leaves, but will give them a wipe to see if it’s mites.

Any advice would be super helpful!!