All 4 thermometers are different temps *pics*

[xenon]

This is rediculous. Witch one is correct?

[az]

lol this is too funny, do an avg i guess!

[Alchemist]

I'd get a clinical thermometer and check.  I'm always worried about the accuracy of these things.  The only thermometer I ever trusted was a foot long mercury filled lab one I had....but I didn't like the idea of it breaking.

[xenon]

I'd get a clinical thermometer and check.  I'm always worried about the accuracy of these things.  The only thermometer I ever trusted was a foot long mercury filled lab one I had....but I didn't like the idea of it breaking.

Where would I get one of those?

[Alchemist]

What the clinical one or the foot long jobbie?  The former from Shopper's or something...the latter from a lab supply place like www.fishersci.ca/ which is Fisher Scientific's canadian website..  PM Shrimpy... he works for them.  They should have some alcohol filled ones which will be less problematic if they break.  Even the digital probes have to be calibrated every now and then to make sure they are bang on.  I had this problem with hygrometers before...I had three...each gave me a different reading...until I bought a refractometer and now I sleep a little better at night. 

[darkdep]

Funny this came up.

I have one of the coralife digitals on one of my 75's, and I've noticed a lot of fluctuations.  I did some reading and realized how inaccurate most of these things are.  I just today got my new lab thermometer from Control Company.  It's got a long probe and comes with a calibration certificate guaranteeing it's accuracy.  I'm going to give it a whirl tonight.  It was pricey, but now I have something I can trust. 

In addition to the coralife, I have the $2 glass ones in several tanks and last night two tanks, reading equal on the thermometer, had night and day temp diff to the touch.

[xenon]

What the clinical one or the foot long jobbie?  The former from Shopper's or something...the latter from a lab supply place like www.fishersci.ca/ which is Fisher Scientific's canadian website..  PM Shrimpy... he works for them.  They should have some alcohol filled ones which will be less problematic if they break.  Even the digital probes have to be calibrated every now and then to make sure they are bang on.  I had this problem with hygrometers before...I had three...each gave me a different reading...until I bought a refractometer and now I sleep a little better at night. 

Would this be a good choice?

http://ecat.fishersci.ca/(balweez2jgke1evm24glgkr3)/Coupon.aspx?cid=203537

[xenon]

[Alchemist]

This would be better

http://ecat.fishersci.ca/(balweez2jgke1evm24glgkr3)/Coupon.aspx?cid=202503  only 22 bucks for the lowest range one which would be fine... and you could use it to see which one of your in-tank thermometers is accurate.  I haven't looked but you should be able to get something like a -10 C to + 50 C range thermometer which would be better.

....but I wouldn't keep it in the tank all the time.  I used to use mine every day to check the temp...just immersed it in the tank and read it off.

[darkdep]

OMG I don't know about the pinpoint, but those coralife's are terribly inaccurate.

If you're going to get something lab grade, get something that has been certified as calibrated.

My new guy I have in place with my coralife.  Coralife = 79.4F, Control = 80.9 F. 

I'm just starting to appreciate how important accurate temp info is.  At 79.4, I was thinking about turning up the heater...when in reality the temp in that tank is perfect and I may have thrown everything off by putting it up 2 degrees.

[Shrimpy]

There is a simple test you guys can do to check your thermometers. All you require is 4 things... a blender, ice, water and a container.

Step 1 - Add ice to blender and grind it up so it is in a slushy state
Step 2 - Put ice in container
Step 3 - Add some cold water (enough for your probe, but not so much the ice melts rapidly)
Step 4 - Stick your thermometer in.

You want to make an ice slurry. Ice slurry has a temp of exactly 0.0 C or 32 F.
You may have to experiment a little to get it bang on, but it is very easy to do.

[Tynan Rasmus]

I have a cheapy stick on LCD, and a cheapy $12 digital, they are both dead on with each other.