A fishkill is dreaded by fish farmers. It wipes out huge investments that could mire them in debt.

Last month’s fish die-off at the Santiago River in Jalisco, Mexico was also a disaster for tourism with the foul smell in the air and the dirty water turning away visitors.

The fishkill was blamed on the toxic waste dumped into the river by manufacturing, automotive and food businesses in Jalisco.

At least 2,000 putrefying carp and crappies were also found floating on the surface of Sloan’s Lake in Denver, Colorado, USA last month. The die-off was blamed by Denver Parks and Recreation on toxic algae blooms caused by consecutive near 100-degree Fahrenheit days, according to the Colorado Sun.

If losing tons of fish is bad, the opposite is ironically not good either in the case of some rivers in Bangkok, Thailand.

The overabundance of blackchin tilapia, an African species, prompted Thai authorities last 13 July to offer at 15 baht per kilo fish caught by anyone to lessen its population, Newsflare reports.

The offer followed the failure of people catching the invasive fish for food and the release of tilapia predators (barramundi) to cut down their numbers and minimize their consumption of smaller fish, roe and eggs of fish bred by aquaculture farmers.

The tilapia infestation is causing losses to some 900 aquaculture farmers in Bangkok and nearby provinces, so authorities prefer to have less of the fish.