Outdoor Tropical Pond heating

[aquaculture]

I'am thinking that if I can find an affordable heater to keep a 300 gallon stock tank in the low 70's in farenheight for the colder months I would change my 300 gallon into a tropical fish tank pond.

The coldest it gets here is about 15f air temp every five years and on average in the low twenties.

Iam hoping that two high wattage fishtank heaters and a tarp tied down on the pond can keep the water at 74f in cold months.
Espeacially if I route the filter strait to the pond instead of the waterfall in winter.

also posted in outdoor pond subforum posted here for more ideas.

Thanks for letting me bounce ideas off yah.

 

[screaminleeman]

I saved my old waterbed heating unit and found that it works well as a pond heater.

I placed inside the plastic preformed pond, and placed the pond liner over top of it.

 

[Potts050]

Just a wild guess but unless you can insulate the tank completely bottom, sides and top you will need at least 2 kW of heating capacity for a 60 degress Fahrenheit differential. Can you move the stock tank into an insulated shed for the winter? Evaporation will be a problem as well....

 

[aquaculture]

I can always shovel mud up around the sides allowing that to dry to dirt to insulate the outside or cover the whole outside of it in great stuff foam.

Clay is the soil around here so a one to two foot layer around the outside of the stock tank would insulate it.

Zyno helped with finding what to heat it with.

I figure if I make a styrofoam lid , with added uniform weight on it, filter will help with gas exchange. Plus I would just need to heat it for at most four months out of the year.

Now I just need to save cash.