My status should be changed from member to lurker...
I should add the conditions that I performed these room temperature water changes. (you've the setup, Deb)
I kept most of my BTA's in a remote DSB 180g sump. the change in temperature would have very temporary because once I had changed the water, I would turn on the main pumps again. Total water volume in the system was about 400g. Water change amount was about 40g.
I don't want people trying this in smaller systems where they could possibly make a significant long term temperature change and shock all the inhabitants.
(BTW, Deb, you should see the size of Foxy these days. She's like a big yellow cigar!)
Mitch