l have been really liking the EcoPure I got with my 510. Only problem is that it needs topping off with a lot of fluid left in the cart. Maybe it's because EcoPure is made with VG and so is fairly thick. Anyone have any ideas how I can get more than 4 drops at a time without needing to top off? I am actually getting less from my 510 cart than my RN 4081.