Thermometer questions?

I think they're both good, to be honest.

I've always used those $2 black strip things you stick on the wall and changes color and have had no problems with it. Plus, it's slim and can be hidden on the side of the tank, which makes the tank look clean.
 
We use a digital therm.it has a probe that has a suction cup on it....about 6 bucks.......:)
 
I'm with Weeser!
 
I've gto one of those stick on strips, and I just got a mercury suction cup one. Mercury thermometers have been around for decades, and are accurate. I've noticed the stick on can be up to 2* different then the mercury. I dont' know if that's because it's on the outside, but ince they're relativly the same price, and I don't think any of my fish can knock it off or break it, I'm going with the mercury one.
 
I had the mercury one first and it works but it looks bad. Then I went out and got the digital one that Wesser and Jojo are talking about. I like that one better because it looks good and it gives you the temp to a 10th of a degree. I use both on opposite ends of the tank. You can never be too safe.
 
I think they're both good, to be honest.

I've always used those $2 black strip things you stick on the wall and changes color and have had no problems with it. Plus, it's slim and can be hidden on the side of the tank, which makes the tank look clean.
Exactly what I have.

What about placement? I have mine directly above the sand bed in the main tank. It's the furthest point from where my return pump feeds water back in...
 
If you have a sump your water should be the same temp across the whole tank/sump since the water is constantly running past the heater, so placement with a sump is a non issue.
 
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