tropical fish in a outdoor pond?

"DD DDD" wrote in message
...
I put my pacu (fake looking pirranah) and 1 tiger barb and swordfish in
my pond and 5 brown clawed frogs after a fish tank leak. After 2 weeks
the frogs doubled in size the tiger barb is fine the swords are ok and
the pacu are huge. I had put (2) 500 watt heaters in and the water is
about 72-74 The heaters help a lot otherwise the water goes to 62 at
night. Can I keep them in the pond all summer? They seem to love it and
the turtle dont catch them. The pond is about 300 gallons. Thank you


Those heaters are going to operate pretty much around the clock. I don't
know anything about brown clawed frogs, is there a risk they could get out
of the pond and go for a walk on their own?

Heating large bodies of water is a fairly expensive process. If you can
afford it...

I suspect my math is probably wrong, so if it is, someone please correct me.
300 gal is 1135.6 liter.
72 Fahrenheit is 22.2222 Celsius.
62 Fahrenheit is 16.6667 Celsius.
# energy needed to raise 300 gal 8 C
1135.6 * 1000 * 8 = 9084800 calories
# 9084800 calorie is 10563.6 watt-hour.

Two 500 watt heaters will pump in 1000 watts of heat per hour, run them for
about 10hrs to heat 300 gallons 8 C, assuming no heat loss to the air and
ground.

-S