Epcor and Alberta Environment are pausing a chemical treatment for invasive goldfish in west Edmonton's Glastonbury neighbourhood, after residents expressed concern it isn't safe.

Up to 25 centimetres long, goldfish in stormwater ponds are often controlled by spraying a pesticide called rotenone — which Epcor says, is the most effective method with no long-term adverse effects. But Glastonbury residents were not convinced.

"As we dove deeper into it, we became even more concerned not only for the…