New bh-100 HOB Reef Octopus, and it foams well, but if I let it go to the top of the cup part it starts to fill up quickly and overflow. So now it only gunks up the tube leading to the cup part and the cup stays completely clear. Isn't it supposed to all go into the cup and not the tube? It's very irritating to clean. I had the same issue with my old one too. What do I do??