Definitely situational.I think maybe it depends on the reason for the PIFing... a lady here was moving, which of course is a HUUUUUUUUUGE pain in the ass at anytime, and she wanted to get rid of a TON of different atties that she no longer uses.... originally she was just going to sell the whole box of stuff for $50, but after I expressed an interest, and my sorrow that I didn't have $50 available at that time, she PIFed me the entire box of stuff -- which easily was $500-$1000 worth of atomizers, when originally bought. Some of it was clean, a lot of it wasn't, and when I opened the box, I got a faceful of stale cigarette smoke from smokers who apparently live in her house. But I didn't look that gifthorse in the mouth, for that quantity of stuff -- I left the box in the garage so it could air out, and cleaned a few items at a time. It was worth it!
Andria
I clean all my tanks whenever I take it out of circulation. For me its just the process if I know I'm wont be using it for a while, I don't like to leave it dirty cause when I eventually put it back in circulation, I'd want to work with a clean tank. Worst yet I would dread to pull it out one day and it leaked everywhere.
...then again I currently only have 3 tanks total and my circulation consists of only two. Couple more should be coming in tomm and the day after tho!