We are away on our first trip in our motorhome and have problems filling up with water.we have a whalemaster system with a small inlet hole under flap.we plugged in the hose and attached it to tap to fill up. Waited ages , checked water gauge and showed less than 25% full. Tried again, same. Warning light came on saying low water. So it looked like water had been going into but it hadn't. I've looked on you tube and it looks like this system is to leave connected but we just want to fill up tank then go to pitch. Can anyone help please? Also how can we add puriclean when we have this stupid system. Tank is sealed from inside so no way to put in additives. Can whale system be removed easily so we can use normal hose?