"Dick" wrote in message
...
On Sun, 13 Nov 2005 21:01:01 -0500, "Bill Stock"
wrote:

I thought there was a thread a while back started by John, who wanted
recommendations for a heater in a large tank. But I googled and could not
find it.

The tank in question has a radius of 34" and a depth of 24", but I'll
likely
keep the water at 18". This is roughly 200 gallons. I tried a couple of
heater calculators on the web, one said 28W (LOL) and the other said 700W.
I
was hoping for less, but I imagine the 700 is close. Although the same
calculator said I need 300-400 watts of light for my 55 gallon. My poor
Cardinals would need sun glasses. I only want to raise the temp about
5°
F on average.


You don't mention where you keep the tank. If it is a heated area,
you can raise the room temperature close to the desired tank
temperature. During this last summer, I set the room temperature to
77F and let the house A/C keep it there. This winter I will need the
heaters as I plan to keep the house at 72F, natural gas heating costs
versus electric tank heater costs being the consideration.

It's in an unheated entryway in the basement. So the temp will be 55-60 on
most days. Ideally I'd like to keep the fish at 60, but 70 would be better
for the plants. These are Goldfish BTW, so the lower temps are not a
problem. But I prefer 60 to avoid any feeding issues.

Trouble with lights as heaters, what happens when you turn the lights
off? I have a 29 gallon with a fully enclosed hood that tends to
overheat while the lights are on. That is with 40 watts of light in
29 gallons of water.


The light will be suspended at least 2'-3' above the plants to prevent
burning. I don't actually know how much heat they will provide. I'll likely
have to build a cover to hold in the heat.

I don't think I understand your problem. If your room temperature is
70F you need less watts, than if the room temperature is unheated and
tends to vary through out the day. You can have more than one heater
in the tank. Lot's of watts means you can heat faster, fewer watts
means the heating time may be longer and not keep up with the outside
changes if those are large.

So, what is your room temperature like in the winter?

House is 68 daytime and 60 nighttime.



dick