too true. goldfish are the worst for wastage! i was holding four 15-20cm goldfish in a 200l tank for a few days, and i had to change 90% of the water twice daily, morning and night, just to stop them from stinking out my bedroom - but it still stank!
did i tell you about the time i had one of them out of the water, in my hand, upside down, trying to vent it to determine gender, and it peed this long warm jet of stinky wees all up my arm past my elbow...?! haha!