Puffer fish has something under his skin

[Saltlife954!]

Hey guys anyone have any clue what this could be on my puffer? I treated the tank with parasite meds but I’m a beginner and I don’t know what’s going on I want to help him I have no clue how to please if anyone has any suggestions it’s getting darker and has been about 2 weeks since I noticed it

 

[Saltlife954!]

I will order it thank you!! I will also take my crabs out and put them in another tank

 

[Saltlife954!]

So update nothing has happens yet I got better pics it’s still moving under the skin

 

[Jay Hemdal]

So update nothing has happens yet I got better pics it’s still moving under the skin

That looks about in the same location as it did on 11/19?
Jay

 

[Saltlife954!]

I took it to a fish store and they said it was a flatworm IDK I bought some red stuff I’m not home at the min

 

[Jay Hemdal]

I took it to a fish store and they said it was a flatworm IDK I bought some red stuff I’m not home at the min

Flatworm? That would be a monogenean. These are common fish parasites, but I’ve not seen one that large or move around like that. Praziquantel will control those, not sure what the red stuff you mentioned is…
Jay