I bought my puffer fish Monday July 27th an 1 died last night because they wouldn't eat the pet store said they are fresh water fish and that's what he Keep them in an feed them krill got home they would only eat crayfish feeders I read on here to change them to brackish water so I did that today and I put ghost shrimp in the water an guppies I pray they will survive an be happy oh this my first time having puffers and I have one pacu fish in there with them any advice love to here oh it's a 55 gallon