I have a 250 sundancer and didn't get the hold pumped out on my last outing...there is about 4 inches of liquid in the tank and some of the "blue stuff" - no solid waste. Am I safe if for the winter I dump in a couple gallons of antifreeze and another "blue stuff" packet? I would just get it pumped out but the boat is over by Lansing and I can't find a place anywhere near there that does it.