On the second week of our seaside vacation(won't say beach)and find that our monitor tells us the grey and black water tanks are nearly full. We are careful not to overuse the toilet and use the park facilties for showers and daytime toilet stops.There is just 2 of us and it seems the tanks have filled too fast unless the sensor is wrong.This r v park has only a dumpsite for cassettes so we cannot dump easily unless we pack up and go to another r.v. park.Our van is a coachmen mirada 34 ft.Hoping someone can assist. I remain cross legged . Regards Big Bilko :clown: :bleh: :bleh: