Accord,

The same thing happened to my corgi last fall. We took her to the vet and got some antibiotics for her eyes, it cleared up then came back as soon as the medicine was gone. Turned out she had indoor allergies, since the symptoms started after we had first turned on the heat for the season and we lived in a very old house at the time (so the heat kicked up dust and who knows what else). The discharge went away on its own after a few weeks, and I haven't had a problem since then...
I would take your dog to the vet to find out his/her opinion and maybe get some medicine for her since I'm not aware of any home remedies and you want to be sure what the problem is first. I hope your dog feels better soon!

Pembroke_Corgi