Heater Size?

[svandoren]

Hello!

I am a newbie crab owner and my crabs are pets in my kindergarten classroom. I have a 10 gallon tank and the temperature seems to be hovering at about 70-72 degrees! Obviously, my Zoo Med 10 gallon heater on the side of my tank is not cutting it.

So I need to know what size heater to get now. I've already arranged a return with Amazon for the old one but I have a thirty day window in which to get something new. I would prefer not to spend over $30 on a new heater as, unfortunately, teaching is an underpaid profession. Thanks for the help! You guys are great and all the threads on here have been very helpful answering all my newbie questions.

[Crabinski]

Getting the heat and humidity just right is always something of a bear, especially when you're working with less than ideal circumstances (i.e., classroom vs home, fluctuating room temperatures, etc.).

Like most of us starting out, you probably relied on the manufacturer's recommendation of what size UTH went with a particular gallon tank and bought the 6"x8" suggested for a 10 gallon tank. The rule of thumb for UTHs is to ignore the "by the gallon" sizing and get the largest one that will fit on the back of the tank (never underneath) without dipping too far under the top of the substrate (you don't want to dry out the substrate as crabs spend a lot of time underground and need that nice damp sandcastle consistency). A 10 gallon tank is 20"Lx10"Wx12"H. Considering that you'll want to have a good 6" depth of substrate, ideally you'd want a 6"Hx20L" UTH. Unfortunately, no such UTH exists as most 6"H UTHs top out at 11"L. The next available sizes are 8"Hx12"L and 8"Hx18"L, both from ZooMed/Reptitherm. Using an 8"H UTH will, of course, result in the pad covering a 2" depth of substrate at the back of the tank, leaving the lower 4" unheated. This is still workable as the crabs will have cooler areas to go to in the front of the tank but you'll probably have to mist the top of the substrate more frequently.

As I said earlier, getting that ideal balance of heat and humidity is not easy but I hope this info helps.

[Laurie LeAnn]

Keep the one you have and just get a larger heat mat or and other small one and double stack it next to each other.. ask other students if they would want to do a penny drive, bring in some spare change to go towards the care of the class crab.

[NeatHedgehog]

As far as estimating UTH requirements, experience with my 10g and 60g tank leads me to say if you have a proper amount of substrate (6"), you wrap foil or insulation over the back of the side of the tank you put the heatmat on, and use a mostly-sealed lid (plywood, glass, covered with plastic wrap, etc, anything but a bare screen), you can get away with about 1-watt-per-gallon when you have less than 20 degrees Fahrenheit to make up (so if the ambient room temperature stays at least 63 or so).

It's not a perfect estimate and I don't know how well it scales for anything much bigger, but in the 10g-60g range it has proven accurate for me.

[JulesRolyCrab]

A 10 gallon tank is 20"Lx10"Wx12"H. Considering that you'll want to have a good 6" depth of substrate, ideally you'd want a 6"Hx20L" UTH. Unfortunately, no such UTH exists as most 6"H UTHs top out at 11"L. .

Actually, there are 6x17 inch Ultratherms. I have one. They are not available on RetileBasics, nor Amazon, but you can get them on the Bean Farm. You'll have to pay a bit more shipping, but it should still be well under $30...

EDIT: The Bean Farm itself is actually on Amazon. http://www.amazon.com/Ultratherm-Under- ... B005PU0EVK

Apologies, apparently it is more than $30, seems that prices have gone up.... :/

EDIT #2: When I try to access the Bean Farm, I get an alert warning me of attackers/stolen credit card numbers. Be careful, you can't access the website (or at least I can't), I would be careful of the Amazon Bean farm store. Anyone know what's up?

[amart24]

I use the large of http://zoomed.com/db/products/EntryDeta ... SearchID=5
8" x 18", works perfectly on my 10 gallon.

[Crabinski]

Actually, there are 6x17 inch Ultratherms. I have one. They are not available on RetileBasics, nor Amazon, but you can get them on the Bean Farm. You'll have to pay a bit more shipping, but it should still be well under $30...

Thanks for the info, @JulesRolyCrab. When I was Googling UTHs, I wasn't able to find a 6" size longer than 11" listed, regardless of manufacturer.

[wodesorel]

I have perfect heat (83-78 back to front) all winter long on my 10/15 gallon (upgraded last winter) with an 11x11 Flukers heater. My local Petco has a clearance section and has them on sale regularly for $15, otherwise I think they run around $25 at a pet shop.

It will dry out the substrate around it since it's underneath, but it also helps to boost humidity since it's constantly evaporating into the air. Just have to watch diligently and re-wet as needed. That 10 gallon barely ever needs messed with, it's the easiest enclosure in the house even though it's in the coldest, draftiest spot.