On a side note,you posted today in cyprinids,that you had a danio die,and this is a new tank,barely a few weeks old,you are not cycled,and buying puffers very soon,will lead you to killing all your fish by ammonia/nitrite poisoning,so why kill them because you have no use for them when your stupity of not listening too advice given to you by curiosity about fish in cycle.
Sorry i don't mean to offend,but it makes me so mad when people say stupid things to fish lovers about killing fish for the sake of just disregarding them like rubbish!