hi,few month back i notice something funny in my tank,at first it took shelter on top of rock in a hole,only to come out at night,so can't get a clear view of it, it look like somthing with lot of leg like a spider n a size no bigger than a twenty cent coin n very sensitive to light,only come out at night, recently it change position n was able to take a shot of it,can anyone ID this thing,gd or bad?