Which is better for ferm. temps?

So I have read a lot recently that the contact with a cool concrete floor in basements acts as a good source for cooling fermenters.

Right now I ferment in a swamp cooler in my basement and keep the fermenters at about 63 degrees when the ambient is 68 pretty much year round.

So my curiosity wants me to ask "Which is a better source for cooling fermenters, a swamp cooler or a concrete floor of the basement"

I don't have probes to measure the inside of fermenters so I am thinking about adding plain water to two nearly identical fermenters I have, putting one in my swamp cooler and leaving one on the concrete floor. I would measure the temps with my floating thermometer (it is calibrated and accurate).

If I find any significant data I will try again with different style buckets (Some of mine are flat on the bottom and some have a raised lip)

If anyone has any experience with this or any suggestions on a solution to put in the buckets that would be better than plain water (ie salt water, etc).

Without a doubt, the swamp cooler is better, purely for the fact that you can add or subtract heat to maintain temps.

That's not to say that you can't make fine beer fermenting on the floor, but people seem to ignore the fact that maintaining constant temp during fermentation is just as important as getting it cool in the first place.

That is why I use a swamp cooler right now. I maintain the temps stringently for the first 1-2 weeks of fermentation then I let it warm up a bit by not adding any more ice bottles once fermentation is either ended or near the end.

I just want to see if I can acheive the same thing without using as much energy by refreezing bottles a few times a day. Plus it would be much less work and if I am out of town the concrete floor method would maintain a more constant temp.

I could also raise the temps a little by taking the fermenter off of the concrete and puting it on an old rug.

I'm not trying to make a widespread change in homebrewing technique...just curious!

I know swamp coolers can be a huge pain because of all the maintenance required. Remember, the most important times for temp control are in the first 3-4 days of fermentation. If I were in your situation, I would be maintaining during that time, and then taking it out and letting it free rise. No need to keep it at 68 when the beer is done. In fact, I usually raise my ferm temps by at least 4 degrees by the end for cleanup.