Ok so I just bought the Herekles Sub-Ohn tank and the rubber O-ring will NOT come out of the glass tank. Aggravating to say the least, as it's the only way to fill the dang thing. Since you have to remove it to fill the tank, I'm thinking the irritation factor may make this thing more of an annoyance than anything. Thinking ahead, do they sell replacement o rings? Thinking my clutzy ... will end up ripping it while trying to take it out (considering the juice capacity of the Herekles may mean I'm sucking up tons of juice and need to re-fill often) . Any thoughts?