UPDATE: I saw this thread pop up and realized I never updated it with my repairs.
The problem was the improper connection made by the plumber I hired. They used Fernco Couplings to connect the pipes to the 2 Liberty Grinder Pumps. The couplings failed immediately, and because I did not fully drain the tank, I went in the other direction, looking to clear a clog in the line. I hired a company to put a camera down the pipe; all-clear. Once I pumped the tank dry ( for the third time), I saw the failed couplings. We then hard-plumbed everything, eliminating the rubber couplers. Problem solved. The 'new' plumber re-built the lines leaving the pump chamber, making the pipes flow together with smooth, 45 degree angles. He also installed a removable cap up high so I can drop a sump pump in and pump the tank manually if I need to.
i learned alot about hiring the right company for the job; you would think that after so many years in business I would know how to research and hire the right company, but instead I hired the wrong people and lost 1 month revenue for the car wash.