severum hole in head

I rescued a tank with some severum and flag cichlids and the severum seems to have these white things kind of breaking out of his skin. I think it's white spot but is it so big because he's a big fish? They look like big white heads but then the skin breaks and it looks long. I can't explain too...

Poor photo I know but is this hith? I noticed it a few weeks ago hasn’t really grown much but has got whiter , water parameters are the usual after 6 days with 40ppm NO3 it’s being changed tomorrow Any treatment will have to be done in tank as my QT is just not big enough , any ideas on what...