Cory with cuts?

[Desastre]

So as I was feeding my fish this morning and noticed one of my corys had like cuts on it side. Can't really figure out how he did this or if he is sick. I ran a test on the water and the parameters where fine at 0 ammo and trites and 5 trates if that. I did a 50pwc just incase but not sure what else I can do for him. Here are some photos I took with my phone to see if anyone can help.

 

[Desastre]

Also he is eating and shoaling with the other 5 corys like usual so don't think it's life threatening.

 

[Crypto]

Hmm, is there any sharp objects in your tank? Well, one suggestion is you could up your water changes by doing a PWC once a day. The cleaner the water, the faster the healing...

 

[Desastre]

I thought maybe the driftwood but even that didn't seem sharp to me. I would expect maybe a good indication of something being sharp would be my betta shreading it's tail but that's never happened.