Who to believe?

[thbjr]

I bought a hygrometer with my first 10 gallon terrarium, a Critterz, at the pet shop for $6. Today I found a Springfield digital thermometer/hygrometer with high/low readout at WalMart for $6.50, but since the readings were so differant, while I was at Lowes this evening, I bought a cheap, $3.50, combo. I put all three side by side in my house and then in a container with wet paper towels heated on my terrarium light hood to raise humidity levels. Last I put them outside.
The hygrometers compare as follows:

1. Combo Digital Critterz Temp
2. 37% 30% 47% 75F
3. 62% 48% 62%
4. 75% 58% 70% 80F
5. 98% 72% 83% walls and lid fogged up
6. 95% 75% 85% 87F
7. 84% 83% 72% 92F removed from heat
8. 108% 68% 80% 85F
9. 110% 75% 87% 79F picture taken
10. 110% 84% 94% 75F 15 min later
11. 36% 43% 53% 44F

This last set of readings is from outside. The Weather Channel says the humidity at the airport is 29% and 48F while at this local home station, (much closer to my house) it's reporting 44% and 38F.

Soooo, which hygrometer do I believe? The round is the Critterz, square is the digital and the combo...is long, LOL!

 

[xvart]

Isn't it impossible to get higher than 100%?

xvart.

 

[thbjr]

Isn't it impossible to get higher than 100%?

xvart.

I always thought it was, but you can see the hygrometer

 

[xvart]

I'd throw out the big white one. The other two seem to be relatively close (~15% difference).

xvart.

 

[D_muscipula]

good thing i dont have a thermometer on my tank haha this is hillarious.

 

[thbjr]

good thing i dont have a thermometer on my tank haha this is hillarious.

Yeah, I'm about raedy to pitch all 3 of them. The round Kritterz never gets below 50%, the digital I can't get over 85% and the long thermometer/hygrometer...110%?, come on. There doesn't seem to be any pattern to them either. I mean if they all rose and declined at say 10% humidity differant, I could see it, but look at the differance between #7 and #8. Go figure

 

[poolboy101]

Heres a easy way to figure out the actual difference. Put the hygrometer in a plastic bag with a salt solution. make sure there is enough salt so that not all of it dissolves. (about a 1/4 cup salt to 1 cup water) Let it sit over night. The reading should be 75%. Then subtract it every time you read it or use a screwdriver to fix it. (DO NOT get the salt water on the hygrometer!)

 

[scottychaos]

I would suggest throwing them all away and not even worrying about the humidity!
in an enclosed terrarium, it will always be "high enough"..
thats all you need to know!

Scot