Plastic Tub and UTH???

I am currently using a 15g glass tank and I want to switch my BP over to a larger plastic tub along with using a UTH instead of an over head heating lamp. Will this be good or will the UTH melt the plastic? I also want to know how many watts is good when it comes to the UTH, I was thinking 4 or 8 but i dont know if 8 is too hot or if 4 is too cool, etc.

Like with any heat source regardless of the enclosure type you MUST use a thermostat, do not use an unregulated heat source.

As long as you have a reliable thermostat set to the correct temperature, melting plastic should never be a problem (a UTH will also reach temperatures that will roast your snake long before it can melt plastic). The temperatures that a ball python needs for belly heat are lower than your core body temperature, so if your UTH is set within the range of 86-92F there is no chance that could melt plastic or cause it to release toxins or anything like that.

I'm not too sure about wattage, I think it depends on the size of the UTH. Larger ones will have higher wattage. But at the end of the day, all of them, even the smallest one, can burn your BP, so whatever you choose, just make sure you have a good thermostat connected to it.

Hope the switch to a tub goes smoothly! It's much easier to get temps and humidity right in tubs and I'm sure your BP will appreciate that.

If you are switching from a 15 gallon tank, I am assuming you have a baby bp (Less than 200g?). I would start with a 6qt tub or no bigger than a 16qt tub. It may appear small compared to the tank but babies, more than adults, need to feel secure and moving them can stress them out easily. Secondly, you will find it is a whole lot easier and lighter to clean a 16qt tub than a 41qt (although not as heavy or annoying to clean than a tank). The overhead lighting must have a thermostat as well.

If your room temp is around 77-80F, skip the overhead light and use the UTH with a thermostat. If your room temp is cold, you can use a 2nd UTH or I would start with a 5watts bulb or smaller. Play with it using a temp gun or digital thermometer to get the temps you need for the right wattage. You may also utilize a stand that would move the bulb farther or closer to the tub to achieve the temps. Lastly, there is a thread somewhere that teaches you how to set up overhead lights and tubs. You must use the lid to keep the tub locked and secured.

If you can hold the plastic tub and it doesn't melt you are all good.
A properly regulated UTH on a thermostat doesn't get hot enough to melt plastic.