Thanks guys, really helps!
rcoute, those rings fit and work well in your BB?
I wonder if there's a more durable material out there that we can use, something that won't get sliced up so easily. Any ideas?
Silent, do you use a drip tip on the end of your carto when you are inserting it into your tank? I've found that this keeps the carto from chewing up the o-rings. I have an older straight delrin one that I use, but those skinny ones made for refilling DCT's would also work. Really, any that are the same diameter as the carto and could pass through the tank would work.
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