Posted: Sun Nov 18, 2007 1:55 pm
A huge pond (I envy you, Terry! LOL) wouldn't have as much of a temp change as smaller ponds & would do fine w/ just the 'help' of a de-icer. Smaller ponds need a bit more though cause they cool faster (& warm quicker...) I'd be nervous about anything under 300 gal or so w/o a heater.
I have a 120 gal w/ 2 200 watt aquarium heaters. I know they're prob not supposed to be used outdoors (doesn't specifically say not to on the package though.....) but the pond is right next to the porch, so nothing will get wet that's not supposed to be wet. My heaters are fully adjustable (Visi-Therm) and has so far kept the water as warm as I need it. We've only had 2 cold nights so far (in a row - 45 & 47 degrees), so I adjusted the temps up to 86, and when I checked in the AM the water was about 75. We really don't get much colder than that where I am, so it works great. I just adjust higher than needed on really cold nights, and back down in the AM.
Tamara
9" f pen cooter-Liza; 5" m RES-Mercer
5.5" f ornate dbt-Lucy
2 3/4" missi map-Jimi; 1.5" painted-Bob
1 dog, 1 cat, 1 bird, 3 kids, 1 hubby
"My mother had a great deal of trouble with me, but I think she enjoyed it"
--Mark Twain--