Premier Anna Bligh may have touted fluoride as the answer to children’s dental problems, but what about its effects on freshwater fish?
This is the question Bli Bli resident Penny Phillips would like answered after nine of her goldfish died within hours of her changing their water.
Mrs Phillips, who had kept some of the fish in an outdoor pond for the past seven years, said she changed the water regularly and had done so twice in the past 18 months without complication.
But on Sunday lunchtime, after changing only some of the water over, she came back to check on the fish and found them dead or dying with the remaining three fish now not looking “too healthy”.
“I’ve had these fish for seven years, some of them, and I’ve never had any problems with them at all,” Mrs Phillips said yesterday.
“I would like to know if anyone else has had any problems.”
UnderWater World general manager Julie Cullen said that without testing the water it would be difficult to know if fluoride was to blame.
She said that since fluoridation was released into south east Queensland water supplies, UWW has adopted protocols to monitor the amounts of fluoride in the water after speaking with council and various fish experts.
“There is no doubt that fluoride and chlorine, which are dosed into our water supply, can be lethal to certain species of fish when in reasonable quantities,” she said.
“Generally speaking, the levels of fluoride that UWW will be exposed to; will be safe for most species based on a moderate hardness of water.
“However, certain species have a greater susceptibility to the effects of higher levels of fluoride in water and additionally, under certain circumstances, the toxic effects of a given concentration of fluoride may also be stronger.’’
“Accordingly, we have developed protocols to monitor fluoride levels exactly the same way that we monitor all water quality components. And as a fail safe option we have fresh water tanks for this water supply.”
Ms Cullen said that there could be a number of reasons for the sudden death of Mrs Phillips fish, including a change in the ecosystem.
UWW curator of fishes Clint Chapman said anything from a rapid change in temperature when adding new water could cause fish mortality and added that UWW have yet to detect any levels of fluoride that would have had any impact on any of their fish.