Heaters that can run on a sealed lead acid battery?

[FlyPenFly]

I would love to go with a generator but unfortunately it's impossible in my NYC apartment to do so.

So I'm good for powerheads running on backup power directly hooked up to sealed lead acid batteries. This should go 2-3 days.

What about for heaters? I know if I were home I could heat up bags of water and put them in the tank but that's not possible if I were traveling or at night.

For keeping 65 gallons at 74 degrees for 2-3 days, what sort of wattage would be most efficient and how large of a battery would I need. Let's say ambient room temperature will be 40 degrees.

 

[lnevo]

I know from a UPS perspective when my heaters on vs just return pump i go from 72 minutes to 7 on the display. I know thats not accurate but shows somewhat the difference in power draw. I too have a 65g with a 200 watt heater. Keep in mind those requirements have a lot to do with room temperature as well so in the summer keeping a tank at 74 would require almost no power...

Edit: saw you put ambient temp at 40...i say good luck i dont think you would get much time without some huge batteries...someone with the electrical formulae could probably figure that out better than me..

 

[Affordable Aquatic]

You cant do that... easily. Heaters draw relatively huge amounts of power. Going with large and expensive deep cycle boat batteries is the only hope and even then with a giant group 34 boat battery you will end up with hours and not days. Using a 12 volt battery and inverter just doesn't work unless you are heating a very small tank.

Look at this battery calculator:

http://ep.yimg.com/ty/cdn/sports-imports/BatterydrainCalc.html

 

[FlyPenFly]

Darn I was afraid of that... someone should invent a thermometer controlled gas burner or something

 

[Affordable Aquatic]

Well, some people have used pool heaters or household boilers to heat their tanks. Those are generally 20,000+ gallons plus. Not many options for a 65 though.
Luckily heat loss is not all that quick and it would most likely take days before your apartment got down to 40 degrees

 

[FlyPenFly]

Unfortunately I live in one of those buildings with the old steam heat. Sometimes my apt is sweltering hot, sometimes it's cold as bones. So frustrating. Wish the management company just put in a new boiler.