PEA PUFFER HELP! Black spot?

[Graceloe]

Hi, I have a pea puffer who recently got a very dark black spot, I know they normally have spots but this one looks different here’s some pictures.

 

[Rocky998]

Hi, I have a pea puffer who recently got a very dark black spot, I know they normally have spots but this one looks different here’s some pictures.

That is definitely really weird... Usually if a fish is coloring up it doesn't color up like this... What are your water parameters using a liquid test kit?