to answer your original question, if your p. joselimaianus is 2-3 years old it should probably be a little larger than what it is. it may have stopped growing because of the 25g tank you have it in, not likely the cold water.
from the pictures it doesn't look unhealthy or deformed from stunted growth. if you have the option i would try to move it to a larger tank and start feeding it some sinking pellet food alongside the fresh veggies. as they get older they need more protein in their diet.
from the pictures it doesn't look unhealthy or deformed from stunted growth. if you have the option i would try to move it to a larger tank and start feeding it some sinking pellet food alongside the fresh veggies. as they get older they need more protein in their diet.
