Hermann's has one eye closed for about a week

[Scott52019]

i changed his substrate to a better one and have been soaking him more. I even tried flushing his eye out with lukewarm water. I don't know what else to do for him except take him to the vet (which I don't want to do because money). It's not infected or swollen in fact he can open it a little which makes me think there's something stuck in his eye. What should I do?