LIMA, Ohio (WCMH) — Algae toxins can kill dogs within 20 minutes after being ingested, according to Ohio Department of Agriculture veterinarian Tony Forshay. That is the very experience a married couple in Allen County, Ohio had.

Tammy and Richard Cotrell let their four dogs out every morning. If the dogs’ water bowls were empty, they would go to the retention pond in the front of the home. They were a canine family. The matriarch was “Lilly,” “Dallas” was the father, “Bandit” was a son and “Daisy” was their daughter.

On June 22, Tammy said that Bandit began coughing soon after coming inside. To her, it sounded similar to a cat coughing up a furball. Soon after, he began seizing and the Cotrells rushed him to the animal hospital. He died the next day.

The following Monday, Dallas began showing the same symptoms, and then Lilly.

Within 48 hours, the Cotrells had watched three of their four dogs die.

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At first, the veterinarian had no ideas. They ruled out cancer, virus, and rat poison. Instead, they looked to Daisy and realized she had not gone near the pond.

“She can’t stand water and avoids the pond,” Tammy said.

When the vet narrowed it down and asked if there was algae in the water, they realized what happened.

The Cotrells hadn’t been able to treat the water because of the large amount of rain this spring and the pond continuously overflowed.

Forshay stressed to never let your animal drink water with algae in it.

“Just assume the worst,” he said in an interview with NBC4i.com. “It’s too difficult and expensive to test.”

There are more than 10 toxins from algae, some can kill dogs almost immediately.

While the Cotrells didn’t have necropsies on their animals, they are treating their pond to make is safer.

“We have a collar [on Daisy] and we have moved the transmitter so she doesn’t have access to the water,” said Richard. “We hope is a new day that we get relief.”