Yellow leaves in a LC

[iamppdoc]

The leaves on a mature LC seem to be slowly turning yellow. The plant, otherwise, looks healthy, with new growth and healthy roots. The plants are in a lean-to greenhouse, facing south and west. Any ideas what could be causing it and is it bad?

[WhiteRabbit]

too much light ? or it was hotter while in the light than it was acclimated to ? Looks similar to what I get on some of mine that get afternoon sun - they are acclimated to the light, but if afternoon temps are suddenly hotter than they are used to, foliage burns a bit, or looks a bit bleached out

[blackpanther]

I think its potassium just reading a little and that's what I think but don't flush or add anything until you know exactly what it is