The algal bloom wreaking havoc on Toledo's water supply is thriving on the same things that make a happy potted plant: sunlight, water and lots of nutrients.

The harmful blue-green algae feast on nutrients such as phosphorus and nitrogen, which have been entering Lake Erie en masse recently from farm runoff and sewage-treatment plants. The buildup causes algal blooms, and leads to water that can cause rashes, kidney and liver problems, as well as throw off the ecosystem.

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