Hi and welcome. The flooding is probably caused by a poorly manufactured coil, or perhaps you have ejuice that is too thin. A juice with a higher VG content might fix it. The tank that comes with that machine is the Toptank Nano, which is manufactured in two versions; 1.9 and 3.2ml. Both are 18.5mm in diameter, the bigger one is just a bit taller. It might be possible for you to find a conversion kit. The only difference is a taller chimney and taller glass. This would save you the expense of a new tank. Another option is the Toptank Mini, which is the same tank but 22mm diameter and a tiny bit taller still for 4ml capacity. It will overhang your battery by 3/4mm all the way around, but that's going to be true for most larger tanks as well; 22mm is a standard diameter. Another good point is the Mini will accept the RBA base so you could build your own coils, if you want, at a considerable cost savings.