Found the missing AE Today, I suspected that it was on the way out as it did not eat and remained skinny the whole time. I dont attribute the death to params because the other AE is fat, very active and pooping up the whole tank!!
This is actually a good thing as i didn't want too many AE's because i want Ottos instead. So 1 AE and 3 Ottos should be good enough for suckers types.