It wasn’t the gravel, or scratches. it was ich I used a second treatment and its clearing up i got this eel a couple days ago no visible signs of anything and he messed up my whole tank with his ich it was not visible when I got him at all so I figured he was good I should of quarantined him before putting him in my tank big mistake I’ll never make again my ph is 7 everything else in at 0 or 2 ppmIsnt keeping spiny eels in a tank with gravel not advisable for this very reason?