Ok, for you Secondgen here's a pic of the overflow, and I added in a picture of the refuge with the overflow box, and the piping for it that goes into the main tank, the pipe with all the holes is the exhaust, it's actually supposed to sit with the holes just above water level, to let most of the air escape, but I bumped into it trying to take a pic of it, but it gives you an idea of all the bubbles this little bastard creates.
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