Thank you both for your replies. I think our EN got scraped when he took over the crayfish cave. Our crayfish died recently, so opened another hiding space. The EN has to get in/out sideways, so I think thats when it happened. It is a 60 gal
tank with a Fluval FX4 canister filter. I do water changes weekly and filter changes monthly, though I think it's time to change the tubing.
I know not to put meds in the water. In my ignorance when we first got them, I did just that and we lost one.