Peter James wrote:
I have a sweet pepper in a pot in the conservatory. Some of the leaves
of the plant are going a blotchy yellow. There are aphids present on
the plant, but I feel that maybe the leaf discoloration is a separate
issue. Can anyone advise me on this? Thanks,

Peter

Are they the lower leaves,Peter? Could be magnesium deficiency.
Try watering with Epsom Salts.
Sam.