Hey there. The solar blanket only works when it is floating on top of the water. I'm not sure what they intend for you to do when it snows. I couldn't get the second site to come up. Sandy

I built a solar heater for my pond three years ago. Mine was for a different purpose, so I don't know how helpful my experience will be to you.

My pond is deep and is usually covered in hyacinths in the summer. Consequently, my pond doesn't warm up much in the summer. The hyacinths are very good at shading the water, and the soil sucks heat out of the water at an unbelievable rate. Without the solar heater my pond wouldn't get above 70 degrees, even on the hottest days. I have one fish with carp-pox so I try to get the temperature higher than that if I can.

My external heater consists of a pump, hundreds of feet of half-inch poly tubing, and two 4x7 surplus sliding glass door panels. The pump is on a timer that turns on around ten, and shuts off around sunset. You would think this would significantly raise the temperature of the pond, but it only increases the temperature by two or maybe three degrees. The problem is the deep pond is in intimate contact with the soil that sucks the heat out of the water.

I only use this system in the summer, since it would freeze up in the winter. Two lessons that might be helpful to you are: First, the soil sucks heat. Second, you don't get as much heat from the sun as you think.

In the winter it is the soil that provides heat to keep your pond from freezing, but if you start heating the water, the soil will take it back. I'm not sure how far ahead you can get in Indiana in the winter.

Good luck.

Very interesting Larry. I have my pond covered with a vinyl translucent tarpaulin, which is supported by a simple 2X4 frame. The whole thing is sloped down from about two feet at one end to ground level at the other.
This keeps the winter winds off the pond's surface.
Without going into too much detail again, I circulate the pond water with a small GPH pump, via the bottom drain piping to a 50 gallon sump barrel and back to the pond where it keeps a large hole in the surface ice open for gas exchange purposes all winter.

I have a hatch cover made from a piece of EPDM liner,[approx 18" X 24"] installed into the tarp that I can lift to check on the pond inhabitants over the winter.

When I lift this hatch cover there is condensation on it and also covering the inside of the tarp.
I can feel the warmth of the air coming out of the opening when I lift the cover off. It is certainly warmer than the air outside of the tarp covering.

I believe there are two sources of energy warming the pond water, one from the circulating water and one from the sun.

The underground piping run is over ten feet long and is four feet below the surface. The sump barrel the piping connects to is buried three feet into the ground.
I believe it and the piping act as heat collectors from the surrounding soil,which is below the frost line. The plumbing acts the same way as a heat pump coil used for home heating.

The tarp keeps the cold wind off the pond, as I already stated, but also gathers heat from the sun,just the same as covering a compost pile/box with plastic sheeting. Where the energy in the form of heat, drawn from the sun helps the break down of the compost material.

I looked in to-day at the pond and there is the start of some ice coverage, sort of slushy at present, but the plants on the pond's perimeter are bright green and better looking, than when I covered the pond over a few weeks ago.

So the cover and the water circulation I would say are working for my pond in keeping the air and water temperatures quite temperate.

I have been doing this for years and it is the same thing every winter, inside that covering, there seems to be a micro mild climate maintained, that the plants flourish in. As do the fish, because they grow bigger each winter.
"Horton"

A solar blanket does help, and it doesn't have to be on the surface of the water. Laying on the surface of the water isn't the best idea, because a fish can accidentally flop its way ontop and not be able to get back into the water.

I've seen several people build plastic-covered structures every fall to cover their ponds. They take them apart and store them come spring.

I'm looking at some sort of solar heater with a heat exchanger just for the 6 weeks or so the pond dips below about 62F. A solar blanket may be enough, I'm trying that first. No snow here so I don't have to worry about a peaked structure.

Some people use stock-tank heaters to keep the ice layer on the top from freezing over, for gas exchange.

i put a green tarp over my pond (formal round with a tiered fountain) i do it to protect the fountain not the fish. my pons in concrete and partially raised. it also has a open portion because the dog will only drink out of the pond. we are in our second week in the teens and i have no ice. the air temp under the tent is easily 30 degrees warmer at night and downright balmy in the day.

hoovb, what kind of fish do you keep in your pond, angelfish? you are in zone 9 and want to heat your pond? if you have goldfish or koi, they are fine without (most wont breed unless they spend several weeks below 60. they can take it. just stop feeding them protein rich food below 60 and not at all if they stop surfacing (usually around 50). i have never lost a fish during the winter and my water is in the 30-40s for at least 3 months not reaching the 60s until may. the japanese think it is neccesary for goldfish to have a dormant cold period. your fish have it easy, no need to worry.

Interesting info - a lot of it kinda confirms my sense that even a plastic or solar covering would create some kind of "greenhouse effect". I think even if it only was a 5 or 10 degree difference that really could sometimes be the difference between the pond freezing solid and an air hole left open. I will of course have a deicer in there as well - are those controlled by a thermostat so it would kick in only if its approaching freezing?

Last year I pretty much learned to keep the water fall OFF
as the pond lost all the heat to the exposed cold air and killed off my fish with a pond temp of 38' All that water moving didnt let the ground temp warm a thing.

This year my falls are off and I setup some 2x4" sloping towards the back of the pond, enough for rain to run off. Then I put some plastic 4x8' lattice over the 2x4s. Bought a heavy semi clear plastic drop at home depot and pulled it down the sides and held it with rocks. A couple more 2x4s on top to keep the wind from picking it up and Im good.

Outside its in the 40s and I really wanted to keep the pond warmer than 50. I had bought a pond tank heater but they only kick in at 45 and below, I looked at heaters but didnt want to dish out $300+ and the power.
I also looked into a spa heater but again some cash.

What I did for $60 was bought a new transmission cool coil at the auto shop. Its aluminum with about 8' of tubbing.
I ran a 1/4" line off my UV lights into a 25' 1/4 hose rated for air-compressors so its heavy duty and wrapped in foam pipe insulation to protect it from the cold air.

On the end I connected the tran-cooler coil then returned that back to the skimmer. I clamped it all tight and sunk the coil into my hot tub spa heater return outlet. The spa
temp is set to about 88' and with the slow water pressure it flows down the hose into the coil and back to the pond.

Its actually warm. Right now with the plastic cover on my pond 24x7 the pond is a nice 76' and stable. On nice days I open the cover a bit to let the sun otherwise I just open it to exchange fresh air for about 30min.

The 8 Koi are very happy, Eating food within seconds about once every 2days for now. Ill post some pics later when I can.

So michael-ftw, it sounds like you are using your spa water to also heat your pond? Is the contact with aluminum ok for the pond water?

some photos of my simple "solar heater".

in the summer before the finish work was completed on the exterior. yard still not inÂbit embarrassing.

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the covering. not the open space for the dog to drinkÂwon't use a bowl. the only reason i covered the fountain was that it was easier than dismantling the fountainÂlast year it cracked. next year i think i will make a tailored tentÂsomething like a dome tent without a floor.

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under the covering. i bagged the fountain to keep the flowing water off the tarp. you can see the water cress that was growing in the bowls. it had gone dormant for the winter, but started growing again when i covered it up. there is no ice and the air temp was 11 degrees when i took the photos. have not been above freezing for a few weeks. so cover helps more than just a few degrees.
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Sorry for not checking back on this thread..Re the aluminum Im going to take a chance and say no..Im not running 100% of the pump output into it and with some fresh water changes and also the dose of chemical balancers it claims to zero metals from the water.

So far the warm spa water did heat my pond to a nice 72.
I also covered it 100% of the days and nights with heavy plastic and kept it pretty air tight.

Spa was at 85 and pond 72-74. Fish eating and happy..Tho I did get a $100 hit on my power bill ea month so I cut it back for now. winter wasnt to bad in Fort Worth this year. No snow. Worst is probably over.