With such a large tank, the heat tape won't do anything for the ambient temps. You may need a ceramic heat emitter if the temps in your house are too cold. I haven't needed one in my 20 gallon long tank because it's smaller and I have the top covered mostly, it holds in heat better. I think a foot of the 11 in would be fine as long as that covered 1/3 to 1/2 of the bottom. The thermostat probe gets taped directly onto the heat tape, I use aluminum tape but electrical tape would work too. I get my heat tape, along with pretty much everything else from reptilebasics.com. Rich is great to work with.