Yeah, that's what I have - independent thermometers & heaters. I'm always monitoring them.
Hey, I just realized something - d'oh! I totally didn't think of this. I removed the filters from my 10 gal tanks, so I only fill them with about 6-7 gallons of water & I've been using the 50 watt heaters the whole time. My house is always at 65 degrees, so I have to keep the heaters set pretty high to keep the water temp at 79-80. Cool! This great - if I hadn't asked I wouldn't have realized I was already doing it. Yay!