I might re-do my tank (due to large fish loss) and I always wondered what new fish I can put in it. I considered bichirs and such but I dont have a sand substrate. Well I just came across Caecilians, I always knew about them but I just learned I can keep them in my tank. For an animal of that size I thought it would need more than 48 gallons. Well I might consider caecilians now and I have a few questions. How much do they typically cost? Can they be in a tank with sharp gravel substrate?