frog spawn not growing

i have a frog spawn and my params are good i think. ph is 8.3 cal is 460 no3 is 20ppm, phos is 0 alk is 4.5 meq, mag is 1250ppm and iodine is .6 its been staying pretty shrunken any ideas i moved it to the bottom of my tank because i thought it was my lights. i dont know any more all out of ideas. same with my richorida by the way

 

I too have a frogspawn with about 6 heads, mine also seems to not grow, or very little if any, but water params are good and it always looks healthy, its been in there now for about 6 months, not sure whether they are a slow growing coral, or if you have soft corals in there with them, i understand they can release chemicals to stunt their growth,