Any Science To Heater Sizing?

[Marcosreef]

Greetings,

What would be the minimum heater size required for a 75 with a 20 gallon sump/fuge? The Mag 12 and LG 3MDQX-SC would add some heat to the water. It's a basement room so it gets pretty chilly 50*F.

I was thinking 2 x 150 or 200 watt Visi-Therms on a Medusa controller. (No room for a Titanium heater, just won't fit and can't seem to find a controllerless model under 300 watts.

TIA, Marco

 

[CraigLampe]

well, as long as you put this in the sump/refugium I don't think you could go wrong with about 300W, I think I would be a little weary of 200W or less, but I just placed a heater in my tank finally today!!
(see post on thermoelectric chillers where I actually realised my tank is too COOL this time of year!!!)

I have a 125 with 30 sump and a 300W heater... this should be enough I would think, usually not a problem with the MH's Heating the water LIKE CRAZY EVERY DAY!!

 

[CraigLampe]

oh, and don't worry about trying to get a "controller-less" heater for use with a medusa (or other) controller, just CRANK THE HEATER TO MAX AND THEN THE CONTROLLER WILL HAVE FULL CONTROL!

 

[Desolas]

For every 9 degree F difference in tank water vs. ambient air there should be 4W of heat per gallon. Up to 12W for high agitation/large surface area tanks.

So if your room is 72 degrees, and your tank is 82, that is 10 degrees difference.

4 * 95 * .9 = 270W.

You don't have 95 gallons of water, but it is best to err on the side of caution, you can't have too much heater- so a 300W heater would work fine, or two 150W would work well also. I use a single 300W heater on the same setup myself, I prefer two heaters if you have the available sockets; just in case one fails you have something keeping the water warm.

While your lamps will do a lot of heating, they aren't on at night, and the temperature can drop fast. You can easily over-work a low wattage heater, it may do the job, but it will wear out faster.

 

[Marcosreef]

Thanks Desolas and Craig.

Super!
I will go with the 2 x 150w Visi-Therms then. They will fit the 13" width of my sump. (Heater length on the 150w model is 11 3/4" with control knob).

Thanks Again, Marco

 

[Anonymous]

Good choice going with two smaller heater instead of one large heater. It has been my experience that half the time heaters fail by getting stuck in the on position. Having one large heater stuck on wil fry your tank overnight. Having one small heater stuck on will make the tank a lot warmer but it will give you time to notice.

 

[aquarist=broke]

Hey,

You might want to do a search on VISITHERM thermometers as they have a bad rep for electrocution and other malaties....

 

[danmhippo]

Errr, stay out of glass heaters. You don't want to have the glass tube bumping in the sump, break, and electrocute your fish and yourself. If you have GFI, chances are everything will shut off and you are left with a heatless tank.

Get a titanium heater. Better to be safe than sorry.

 

[Marcosreef]

Jimmy,

I would love a titanium heater, but I can't find one that's controllerless, and that fits my sump. (13" max)

Marco

 

[ChrisRD]

Jimmy,

I would love a titanium heater, but I can't find one that's controllerless, and that fits my sump. (13" max)

Marco

Hey Marco:

The Won Pro-Heat Titanium heaters might work for you. Lengths are as follows:

100/150 Watt = 11"
200/250 Watt = 11.75"
350 Watt = 12.5"

I got one from Premium Aquatics for a friend. I've also seen them at Marine Depot. My friend's seems to work great. I'm thinking of getting one myself to replace my glass heater...

 

[Marcosreef]

I am wondering if the controller can be removed and a male plug spliced on the heater element. Not sure how exactly the Won heaters work. If the element gets the full 120v current, or does some other funky microprocessor stuff...

Marco