Cucumber leaves turning yellow
I'm pretty new to gardening and this year I decided to start my plants indoors from seed. So far so good, but in the last week all 3 of my cucumber plants have their bottom 2 leaves starting to turn yellow. These are not the cotyledons leaves (which already started to shrivel so I pinched them off about 1 week ago).
What might I be doing wrong? I have tomatoes that are doing great and a zucchini & melon plants that are doing well. I transfered the seedlings about a month ago from the seed sprouting trays to 4 inch cowpots and have them under a grow light I borrowed from a cousin.
I thought maybe I was overwatering because it's hard to tell with the cowpots. This past week I just put a fan on them to help with air ciruculation.
Any other ideas what I might be doing wrong and how to fix this? Should I cut off the wilting leaves? I have photos I could post, but am new to this forum and haven't figured this out yet.
Any help would greatly be appreciated!