Three people are facing up to two decades in prison over a $1 million toilet paper scam in South Florida.

Federal prosecutors say the trio duped elderly customers into buying unnecessary septic products, in some cases more than 70 years worth of toilet paper, the Miami Herald reported.

Salespeople for FBK Products allegedly told more than a dozen victims they needed to buy the company’s special toilet paper to avoid ruining their septic tanks, claiming the federal government had changed regulations on toilet paper.

They said the company was affiliated with the Environmental Protection Agency, the U.S. Food and Drug Administration and the U.S. Department of Agriculture, the Herald reported, and even claimed one product -- the $199 Septic Remedy treatment -- would eliminate the need to have tanks pumped.

Victims were also told that they needed special soap, detergent and toilet paper or their septic tanks would not pass federal inspection, prosecutors say. The federal government does not regulate septic tank products.

The three pleaded guilty in federal court last week to conspiring to commit wire fraud and will be sentenced in February. Three other employees are awaiting trial.