Hello, I've recently noticed (over the last week) some brownish-yellow spots appearing on my leaves. I've looked through some help guides but it doesn't look like any of the deficiency pictures.

Also, the stems are mostly green but on the spotted leaves they've turned reddish-brown.

More pics in my grow diary.... http://www.uk420.com/boards/index.php?show...p;#entry1850925

If anyone has an idea what this is, please help me.