Seems to me that this survery is very inaccurate. It isn't poll to determine what enclosure bp's go off feed in, but a poll of what people are housing them in.

There are way too many variables. First -- someone using a tub may be doing everything right as far as husbandry, and the person using a tank is doing everything wrong; or vice versa. Secondly, if a ratio of 2:1 (for example) of all the people taking the poll are using tubs, then that would lead one to believe that a ratio of 2:1 would have bp's off of feed.

In order for this poll to actually work, all tanks and tubs set up would have to be exactly the same, the husbandry would have to be perfect, and there would have to be an equal number of tubs to tanks in the sample range.

Very good thought, but way too many variables!