Killing him softly with......

Yesterday i did my annual-major aquarium water changing for my smaller aquarium, bought some new tiger barbs (a type of fish). Today, noticed some of them r diseased with white spots around their bodies, bought a bottle of mediation, with few drops (with dual counter-checked calculation of the doses) of d drug, i sent one of them to heaven ....... Oh gosh, instead of helping them, i poisened them. He just did some chinese acrobat in the water and off he went to the moon...... Whuaaaaaa......just thought tht if underdose there will be no therapeutic effect. Unbelievable, my calculation was correct, yet ... hai~ lukily i redo d water n the rest survive. Pheeew~