Effective Thermometer

[laxation]

I have 3 thermometers, a stick on, cheapo digital one and a cheap glass tube one, but they all say different temperatures.

Which one would be the most accurate?

 

[Gvilleguy]

I think it depends on the brand. I would guess that the digital and glass would be more accurate than the stick-on type. Do you happen to have a meat thermometer that would register a temp as low as your tank temp? You could get a "second opinion" from it.

 

[laxation]

I don't have one of them.

Are digital ones normally accurate? I don't know how complicated it is to make it accurate, but either way - the thermometers show 25 and 23 degrees, and I'm going for 24 so I guess that's good?

 

[raptorrex]

I have 3 thermometers, a stick on, cheapo digital one and a cheap glass tube one, but they all say different temperatures.

Which one would be the most accurate?

over the years, on here, the spirit come out better. some people have the odd notion that digital thermometers are in some way more accurate than others. well, that's true if you have a "re-calibratable model (and £100 to burn). but for the majority they are as inaccurate. and get increasingly more inaccurate, with time.

actually, if you average out your three readings. truth is, that's probably close enough, anyway.

 

[Geoff-]

The idea that digital is more accurate simply for being digital is unjustified, everything is built to a price and low price = low quality simple as that. A cheap digital will be built without care and uncalibrated and it could be reading 600 degrees but it looks more impressive doing it.

 

[laxation]

Thats what I figured with the digital ones...

I figured the glass one would be the most accurate, being that its such old technology it must be doing something right to still be used!
but even that one was cheap... i got it while my GF borred the digital one.

 

[Gvilleguy]

I have two different brands of digital ones (about $10USD each), and I checked them against a meat thermometer, and they were both within a half degree. So that's good enough for me!

 

[raptorrex]

and I checked them against a meat thermometer, and they were both within a half degree.

though the meat thermo will be as far out as anything else. possibly further, they tend to be accurate to 10's of degrees.

but even so, its not worth the bother. even, fairly, sensitive fish will be fine, within a variance of several degrees.

 

[Gvilleguy]

Well, it's actually an expensive, calibrated, digital meat thermometer! I guess I should have mentioned that.

 

[the biffster]

i find the glass ones more accurate
the stick on type and the digital
can be as much a 5 or ten degrees either
way i find

 

[raptorrex]

Well, it's actually an expensive, calibrated, digital meat thermometer! I guess I should have mentioned that.

lol, i knew what you meant. but when was it last calibrated? if it was when it was new, and its over 12 months old. its no longer considered calibrated. truly, accurate thermometers are calibrated every six to twelve months. and there is no other way. I have a very expensive Wine thermo, but its no more accurate than one bought for £2. i know that because i have two, eye waveringly expensive, Pro thermometers. oddly i never use them (for fish). there is simply no point. I am lucky though. i have a friend who can calibrate them for me, for nothing. £40 a time, if i had to pay. but for fishkeeping it simply is not worth it, £2 for a spirit is all you need.

 

[Gvilleguy]

I didn't know that about thermos!! You would think calibration would "stick"...

 

[Timmy_Bee]

Does the OP have their thermometers stuck on either end of the fish tank? sounds like a stupid question, but that might have something to do with it!!!

Also, off topic, but has anyone had any experience with in-line heaters set up between external filters and the tank? are they worth it? am trying to go for the 'no equipment' look in my tank.

 

[GrayScale]

To get a better average temp you could also use 1 thermometer at a time and put the in the exact same place for a reading. Depending on circulation of the water in the tank there could be pockets of slightly warmer to colder temps I would say no more than +-2*. temp near the heater being warmer than the temp say at the opposite corner at thebottom of the tank.