Sodium cyanide is often used to harvest tropical fish for the pet trade in non-lethal doses. Fine. For some fish. Others suffer neurological damage, reproductive harm, and other health problems. This decreases their longevity in captivity as well as the overall health of their ecosystem. It limits biodiversity and contributes to the destruction of the worlds reefs-- nearly 90% of the reefs in the Philippines have been affected by humans. I'm no environmental whack-job, and before you call me out, just know I'm getting the word out just because it feels like the right thing to do; I won't hate you or even care if you ignore this, but I think knowledge is often for the better... I love a good reef tank.
So... Just saying, if you care about this sort of thing, perhaps ask your fish store how they get their fish-- these methods are often illegal yet poorly enforced... There are plenty of healthy tank-raised specimens available as well if you know where to look! I'm sure I don't need to tell you all that.
Thanks for reading, if you did.
Have a great day--