Hi guys. I have one of those preshaped ponds from Home Depot at my house. Maybe 100 gallons. I have a lilypad plant in there and 11 goldfish (out of 20 that i bought for 29 cents each). I dont really want to just let the fish freeze because well that's mean and then Ill have to start with real small fish in the Spring again. I assume this will freeze solid over the winter so what is my best option? 1. take out plant and filter and let fish probably die 2. take everything out and keep fish inside in crappy aquarium 3. get a water heater 4. other Anyone know what it would cost to keep the water warm enough to not freeze?