just a little update ... they are now called white and black because one has a completely white tummy while the other one still has a blackish belly.
Both are doing well, the black one eats like a pig when I feed them shrimp and bloodworms, I tossed in a small snail the other day and he devoured it!

I was expecting him to eat the shell but they didn't, do puffers eat the shell or just the snail?
I've moved them into the 29g for now and the white one just loves to move up and down, over and over again.
The feeder guppies I tossed in are all still in there >.< I was expecting them to be gone already but they won't touch them. I may have to move them into my 55g when the guppies get bigger.
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I've also bought 3 dwarf puffers because sadly my one lone puffer that I had for the longest time died this past week

the ones I got from the pet shop are of course too tiny but they're just sooo adorable