LagunaPowerHeat 500-Watt Pond Heater for Outdoor Ponds with Fish – Thermostat-Controlled De-Icer, Safe for Plastic & Liner Ponds, Stainless Steel, 22 ft Cord

I took a gamble of the high price of this unit compared to others on the market. I seem to burn multiple heaters out every season, or their current draw trips my breaker way too frequently. It was time to take heating to a new level. This product has a longer cord and a little red LED on top. Sounds trivial , right? Wrong! Two simple features that are well worth it! I can now place the heater in the middle of my 10x15 pond and I know that it's on from 30ft. away from the light. Awesome! Has performed well and has kept an opening in the ice down below 0F air temp, -20F wind chill.. I wish some other suppliers would catch-up to these simple improvements to bring the price down a bit. I'm hoping to get a second unit in the off season at a lower price. If not, I'll pay full price again in the Fall.

I've been a pond owner for about 12 years and have tried several different types of pond deicers - the green 1500 watt thing, the black 100 watt donut things, the ones you can float or submerge...and more. I have five of these Laguna units, and the oldest ones are 3 or 4 years old.These are the ones I am sticking with. They are effective enough to do a good job clearing a meaningful area of ice, and at 500 watts you can deploy a few of them depending on your circuit. They are also very well built and they LAST. Many of the other ones are junk you'll be replacing every couple of years. I also like that the cord comes straight out the bottom, which helps it sit level in the water. Quality.For you pond newbies, you want to put these in the center, over the deeper areas, and bubblers near the perimeter of the pond - never in the deep part in the middle. Trust me. I killed more than a few fish before I figured this out. And you need BOTH the deicers and the bubblers. Trying to sneak in a mid-winter partial water change is also good if you can do it.

This pond heater was reliable for 10 years. I liked that it had a light on top that showed it was working.This year it stopped working. The price has gone up a lot since I bought it 10 years ago.

We changed our pond winterization scheme this year. We have a relatively small pond (probably 400 gallons) fed by a waterfall, and in prior winters we kept the waterfall running even when most of the pond was frozen over. We'd run a bubbler but no heater. Our 5 koi have done well and grown large enough that our landscaper and "pond people" have all been nervous regarding whether we can keep everyone healthy under any winterization plan. To minimize the risks (to both fish and equipment) associated with running the waterfall all winter, we decided this year to try removing the waterfall pump and just relying on a combination of bubbler and pond heater. I bought the Laguna 500 W heater expecting that we'd see the pond freeze over but retain small open areas around the heater and bubbler.We're now halfway through winter and I've been surprised that the pond has not iced at all. The heater is warm enough to keep the entire pond in the high 30's (37? it's been a couple of weeks since I checked on a very cold day). We were down in single digits again last night with no sign of ice. The fish seem fine resting on/near the bottom and they seem appropriately active on warmer days (40's). The light on the heater has been red 99% of the time or more -- I don't think I've even seen it flash green once during the past month. So I agree with others who have taken off a star based on confusion regarding the significance of the red vs green light. I can't comment on the actual power usage -- given the complete lack of ice maybe this is heating more than necessary. But overall, we are very happy with the heater -- it has brought us a much more worry and maintenance free winter and the fish seem fine. If things stay this way for another 8 weeks we'll be delighted!Update -- the winter season completed a few months ago and I thought I'd update this. I've upgraded to 5 stars because we did make it through an awful winter without any pond trouble. It seemed to be in good shape when we removed it from the pond so I expect to get at least another season out of it. At some point during the winter, we disconnected the power for a few minutes and reconnected it; after that the lights worked much more as expected. Laguna could still do a better job explaining the lights on their website and in the product packaging (my instruction booklet is basically worthless). But that's a small complaint given that the device gave us just what we needed to get through a brutal winter with minimal effort required for the pond.Quick update August 2017: Just checking some old reviews and I thought it was worth mentioning that this heater continued to perform as described above through two additional winters. This past winter the lights did change from red to green in a manner that seems right; but we still had the entire pond clear of ice all winter. In that regard if efficient energy utilization is the most important thing to you I'll grant a yellow flag on this. But if the most important thing is preventing freezing without frying the fish -- what matters most to me -- this is just fine after 3 winters.

It floats which is importantThe green light and red light is a great featureYou know when it’s working

Have had this product through two CANADA winters (e.g minus 30 F or C )Maintains opening in ice even at ultra low temp.Would prefer it have a better sensor to auto shut off when temp above freezing. I bought a separate switch that does that now

great product, Excellent price,

I had ordered two of these, not sure how effective they would be. The LED light on top is brilliant as you can see some from distance when they are on and when they have reached temperature.Its -21 Celsius right now and they are working like a charm.

Worked very well for 2 seasons in southern Ontario. Now the light comes on but no heat-apparently not worth trying to repair and only a one year warranty. Better than the last which only lasted one season...