Thermometer or Heater broken? Or is it just me?

[JourneyReef]

Hi all,

I was futzing around in the tank today and naturally as soon as I finish I notice that my thermometer reads that my temp has climbed to 80.6 which is 4 degrees higher than it should be. I have a heater but no chiller. It's never gone that high before and it wasn't THAT hot here today. So, I'm scratching my head. I think I've solved the problem when I see that amidst my futzing around I knocked the thermometer around and it is floating up by the lights where it is hot. So, I think - there we have it. I put the thermometer back where it always is. Temp goes down. Barely. Crap. Then, temp starts slowly rising! What the heck?? I did wiggle the heater around today so could I have broken something?

 

So, question is - what's causing the problem and how do I fix it?

 

Next question is - what's the short term solution? Right now, I've unplugged the heater (in case it is defecting) and I took the lights and top off. The temp is steadily and slowly dropping - now at 80.1.

 

I'm scared that my thermometer is broken and who the heck knows what the actual temp is. I broke my back up a few weeks ago and my medical/people thermometer won't read that low. Crap. I'm scared to leave the tank tomorrow.

 

Or, perhaps the heater is broken. I have a back up heater so...what to do?

 

ARGH

 

 

Oh - the temp here gets down to 65 at night (yeah, even in the house typically) and up to 80/85 tops during the day.

[veshman]

Well it's really hard to say which is broken... I think thermometer is probably more likely (just found out mine's 4 degrees off), but it's wierd that it would get so off in such a short span of time.

 

Either way, you need to find out which it is. I'd reccommend (assuming you don't have a usable glass thermoneter at home) taking your thermoneter to a LFS (or even home depot...) to check the temperature, and go from there.

 

(It's also worth nothing that most digital thermoneters operate both in and out of water, so you could always just check it with your house thermostat).

[JourneyReef]

Why didn't I think of that! Alright, working on that experiment now. Outside the house it is 68.9, Inside the house it is 79.9 (Ha! That is way hotter than I thought!). My thermometer in the water reads 80.0, and outside the water is reading ...ooops...gotta wait for it to dry. BRB,

 

 

Well it's really hard to say which is broken... I think thermometer is probably more likely (just found out mine's 4 degrees off), but it's wierd that it would get so off in such a short span of time.

 

Either way, you need to find out which it is. I'd reccommend (assuming you don't have a usable glass thermoneter at home) taking your thermoneter to a LFS (or even home depot...) to check the temperature, and go from there.

 

(It's also worth nothing that most digital thermoneters operate both in and out of water, so you could always just check it with your house thermostat).

[JourneyReef]

Okay, so my home thermometer says that the house is 77.4 degrees and my tank thermometer (pulled out of the tank and dried) is reading 74 degrees. Soooo somebody is off somewhere and I just pray it is not both of them in opposite directions. So, I guess I should set the heater to come on around 77? That way if it is reading low, the tank shouldn't get above 80? And if it is reading high, the tank wouldn't drop below 74? Does that make sense?

[JourneyReef]

What are the safe high/low temperature ranges for sw reef tanks with fish?

[smoknta]

My tank will get up to 83 sometimes with no ill effects so far.

[JourneyReef]

Thanks, that's helpful. If the thermometer is right, it got up to nearly 81 yesterday and down to 75 at night...I hope the swing is not too much? I suppose that the swing is accurate even if the exact temperature is off.