I have a little baby porcupine puffer that seems to have changed color drastically since I transferred his white sand for black in his 20 gal tank (the old sand was becoming a huge hassle to clean). My theory is after I placed black sand in his aquarium, he instinctively darkened his skin for camouflage; the other possibility was a spike in ammonia after the sand transfer... Anyway, I also just transferred him to a 35 gal tank a few days ago -- filtration is good and bacteria is there, but recently I also noticed half his belly has a darker tint than the other half.
I miss his cute yellow color!
Quick side note, is petting him bad? Occasionally he lets me gently brush his back with my finger, but I want to make sure I don't mess up his slime coat.
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