Seedling cotyledons look unhealthy

[Bobster]

Good to know, thanks. I think I'll do that in future.

[Bobster]

Thanks, will do! I can’t see the link you mentioned - would you be able to send it again?...

[Bobster]

Does anyone know why the cotyledons look like this?

I’m growing in a cupboard using pre-mixed living soil: https://livingsoilsfertilis...