Me again... another plumbing topic and the second of two things I've found didn't quite check out when I gave my new-to-me 2006 Niagara the ole once over after taking delivery last night. See photo: http://www.flickr.com/photos/runningwithicecream/9284475159/# The red circle in the upper left points to the shower flashing around the shower drain. I saw a small amounts of water dripping from that spot. I noticed this when I decided to look under the pup after having been running water throughout... just to see if I can see any leak issues. And sure there it is. However... I also realized what that clear tube was that been hanging under the pup (lower right red circle). When I looked at the unit, the previous owner wasn't sure what that clear hose was that was dangling underneat. And today... I think I just found out... It must be the grey tank overflow, right? Because in all the running of water... and trying to fill up the water heater ... I must have filled up the grey tank. So when I looked under... and noticed this leak from the shower drain... I also noticed the grey tank was overflowing out the grey tube. Then I realize that the leak at the shower drain may be the result of the grey backing up to the shower. And I assume the shower drain is much like a "catch"... the shower stall floor fittings falls into the drain below... and there's no real seal around it. And so if water backed up... if would overflow and leak out. I think this because I can't get the leak to occur when I just run the shower. Can you confirm this is expected when I overflow the grey tank? And as far as the overflow tube... do I just zip tie that somewhere on the frame?