billd

I've had most of my plants die after using Furan 2, Now if I need to use it, I remove fish to a hospital tank. You have better control and use less Furan as you have less water to manage.

Seems to me that chemicals and freezing would be slow and/or painful. The quickest and most foolproof method I've seen is to drop fish into boiling water (in the net if you like). Death is instant, and clean.

I've had no problems with Siamese fighters with Threadfins, I also keep Fighters with Royal Whiptails. Have a Fighter that chases Glowlight tetras (never gets them) and seen them stalking other fish but normally they take out their aggression on their reflection in the back of the tanks. They will catch Guppies though, depends on the individual Siamese. Threadfins in a small tank dont harm each other but the dominant ones may starve the weaker/smaller ones. They need room to dart about and flash each other, 60L plus tank and plenty of cover because they get nervous.