Imo there very prone to probs whilst juvenile, water perams , stress , tankmates , feeding etc , once they hit the 8" mark there hardy , mines been out on the floor a few times during tank upgrades and once I found him there half dead lucky timing I managed to revive him after an hour lucky lucky , mines survived a massive ammonia spike when I was away on hols (lost loads of tankmates) , never had any probs with healing process when scale loss or cuts and scrapes from tank displays etc , depending on the type of aro I keep jardini hence the username , ive kept silvers there hard but are prone to drop eye , ive heard blacks are bit of a nightmare with water quality and get sick quickly , im no aro expert this is just info that ive discovered on the journey hope this helps you out