temperature monitor

I have one similar
http://www.bigalsonline.ca/catalog/product.xml?product_id=29481;category_id=3231;pcid1=;pcid2=
on my larger tank. I like it, easier for my bad eyesight. :)

I also have one on my water bin, it's just one I bought at Wal-Mart. When I got it and compared it to a couple hang-in thermometers, it registers 2 degrees higher. So with that one, I know if I want 76 degree water, it has to read 78. So, then I bought the above Coralife one.

Just noticed the one I have doesn't have the alarm like the one you pointed to. Nice feature.
 
I use one similar to that as well, I don't know where I would be without it.
 
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