I have an 8 quart flat back bucket with two poultry drinking cups screwed in for their water. I know it will freeze if I leave it and I will be hauling a lot of water. I am looking at different things to purchase and have come across a few - metal heated base, heated plastic waterer, or a heated flat back bucket used for horses. Here's my problems with all of them: Metal Base: I have a plastic waterer and I am afraid it would melt on the heated metal. I would buy a metal waterer but I can't fill the waterers unless they are top fill (always end up soaking myself and just absolutely hate those waterers). So my question is basically would the plastic bucket melt on it? Heated Plastic Waterer: Again, I can only use the top-fill ones and I can't find a heated top-fill waterer. Heated Flat Back Bucket: This is looking like my best option but would it be possible to screw the cups into it or would that mess with the heat? It's also 5 gallons, so much bigger than the one I have now but would work (I'd have to find a bigger space in the coop for it). ETA: I also found this: http://www.farmandfleet.com/product...sion-sinking-de-icer-plastic-tank-heater.html Would that work better in the waterer I already have?