Temp Control

[dskidmore]

It's that time of year again, where I have to worry about my aquarium in my unairconditioned house overheating. I've had good luck with using an open top and a fan, but I'd like to be able to monitor, and possibly control the situtation.

With a controller I could turn off the fan when nighttime temps went below lower bound, and turn off lights when daytime temps went above upper bound. I think a dual appliance controller is likely beoynd my budget though. Might be able to swing a single appliance controller, if I can decide which of the two it's more important to control.

Minimally, a min/max thermometer would help me monitor the situation, and work out simple timers to keep the temp in a narrower range. A data recorder would be better. (I have decent computer skills, so I don't need fancy software, just some type of input to read.)

So, can anyone suggest economical versions of the above equiptment? House rule is I don't have to consult hubby if it's under $100. Over $100 and I have to talk him into it...

I did a little poking around, and all the min/max thermometers I found were not submersable. Plenty of submersables that had alarms, but not this basic recording.

[Ziggy953]

Well the type of control you are talking about comes from a controller.

Have a look here AquaController Jr - Google Product Search

I think you may find what you are looking for and more.

[dskidmore]

Yeah, but after I throw in all the x-10 modules, I'm way over the "don't have to convince hubby" budget.

It is about the best deal I've seen so far though. I just don't see any that monitor without control for less.

I guess I'll work on convincing hubby...

[Ziggy953]

The nice thing about the controller is that it will take care of your lighting pumps heaters and all kinds of other things. You can set it up to shut down the lights if the temp gets to a certain degree. They are very useful additions to a reef tank.

[Kurt_Nelson]

Here are your two best bets for temperature controllers...

Johnson A419ABC-1C 120/240V Single Stage Temperature Control - The

Ranco ETC-111000-000 Digital Temperature Controller - The Ranco ETC

These units are both single controllers. They only control one thing. Ranco also makes a dual controller, which could be used to control both a heater AND a fan, with separate setpoints...

Ranco ETC-211000-000: 2 Stage - The Ranco ETC Store

The links I've provided are for the unwired versions. Poke around the website and you'll find their wired versions, for more money. The wired versions at this website though, do not include making the temperature probe waterproof. If you look around the DrFosterSmith website, you'll find the Ranco controller (both single and dual stage) wired, with the probe already waterproofed.

I've been running the Johnson single stage unit for about 5 months now. Wish I'd done it sooner. Way better control over temperature, and less stress worrying about the bimetallic thermostat in my heater welding itself shut someday and frying the tank. These digital controllers are waaaaaay more reliable.

I bought the unwired version and wired it up myself using an appropriately sized extension cord to give me the inny and outty plugs. I then got some airline tubing of appropriate size (can't remember what it was) and filled the end with silicone. Then I stuffed the temperature probe into the tubing and goobered (technical term) more silicone in there until I had a watertight plug on the end. The other end of the tubing is open to air, but that's above the water level of my tank. I then stuffed the sensor into my HOB skimmer outlet because that was a convenient place for me. Controller kicks heaters on at 78 and kicks them off at 79.

I have also put a clip on fan that blows across the top of the tank on a standard timer. It comes on about 3 hours after the lights come on, and goes off a about 3 hours after the lights go off. That seemed a cheaper route than going with a dual controller, and it seems to work. (Just PC lighting, not halides... but my house doesn't have AC and it can get warm.)

[dskidmore]

Originally Posted by Kurt_Nelson

Then I stuffed the temperature probe into the tubing and goobered (technical term) more silicone in there until I had a watertight plug on the end.

Ahh! Sneaky! I've started work on the hubby. I'm going to go for the Aquacontroller if I can. If not, these others I can sneak under the budget radar with your conversion tips. That's just what I was looking for! Thanks.

[dskidmore]

Hubby still thinking about it...

Today it's supposed to get up above 90. I turned off the lights, and turned on the fan before going to work. The tank is already 80. (I accidentally left the lights on last night after overriding the timing to take some pictures.)

[delco]

I would reccomend that you let the temp go lower at night, so that if you get a 8-10 deg rise in temp it would still be comfortable. I think a fan would help to warm the tank if you are blowing hot air onto the tank.

[dskidmore]

Originally Posted by delco

I would reccomend that you let the temp go lower at night, so that if you get a 8-10 deg rise in temp it would still be comfortable.

A stable temp is more important than a specific temp. If I let the temp go lower at night, then I'd have a sudden temp spike in the day before the fan kicked in.

Originally Posted by delco

I think a fan would help to warm the tank if you are blowing hot air onto the tank.

I believe you are forgetting about evaporative cooling. The fan also pushes away the air warmed by the lights. It's even hotter up in the lights than it is in the house. I have been maintaining the tank at 80 degrees with the fan and my heater.

[dskidmore]

I'm still poking around a little bit, even though I've made a purchase. If you already have a TI-84 Plus, or will need a graphing calculator for another purpose, you can try this. For $42, it contains the probe and conversion to mini-A USB. In theory, if you could write the software, that might be hardware compatible with other USB devices like PDAs or iPhones, although it's only advertised for the TI-84.

Also, if you want to do your own programing you can go for:
Thermocuple - $14
and
USB Converter - $60 (This converts to the right USB port to connect to your computer.)

[dskidmore]

Better Yet:

Go!Temp

This puppy runs $40, plugs into your computer, and comes with free software for Mac or PC.

All you have to do is waterproof, as Kurt described.

[Kurt_Nelson]

dskidmore... guess I misread your post, I thought you were looking for controllers. Seems like that link posted is just a data logger and won't control anything.

delco... think I'm missing something, but a 8-10 degree temperature swing would definitely NOT be a good thing. I'm assuming we're talking saltwater here - maybe it's different with freshwater. A fan blowing over the top of the tank - even blowing warmer air - will lower the tank temperature due to evaporation as dskidmore noted. Even in an 85 degree house, I can keep my tank temp at 79 degrees (and even cause the heaters to come on!), with just a little clip on fan blowing across the top.

[dskidmore]

I'm a computer programmer. I already have an X-10 controller box. If I could plug a temp logger into my computer, I'd have a controller a bit later... Granted, its a lot more work; that is why I bought the fancy one instead.

I'm enough of a geek, I actually looked up how to build my own probe. Thermocouples that are not part of an assembled probe are really cheap. I didn't get as far as figuring out the analog/digital converter, but I think I have the parts for one in my attic.

[delco]

Originally Posted by dskidmore

The fan also pushes away the air warmed by the lights. It's even hotter up in the lights than it is in the house.

I would have the lights off unless you have plants. Or If you do have plants you could run the lights at night when it is cooler. Just an idea.

[dskidmore]

Originally Posted by delco

I would have the lights off unless you have plants. Or If you do have plants you could run the lights at night when it is cooler. Just an idea.

I have plants:

(In the middle of some maintenance, please don't mind the mess.)

And I'm already running an offset light schedule. I run from 1-11 in the winter, and 4-2 in the summer. I still have to acchive a 10 or more degree diffrence between ambient and tank temperatures when it gets up to 95 in the house.