Pythons come in 25 ft lengths - I was farther from my Kitchen faucet to reach it so I had to have the extension to 50 feet (I really only needed about 35 feet total but I had no choice) - after I'm done with changing the water I have to get the leftover water out of 50 foot of hose. That can take me 30 minutes or it can take over an hour depending on what a pain it's decided to be. So re-think how much time you are spending carrying buckets vs how much time servicing the Python. I have the added problem of being on oxygen so my oxygen hose kept getting tangled with the python hose - a problem I hope you never have.
The python also doesn't have any filter that would keep small curious fish from being sucked into the tubing (and for some reason they are really intrigued by the suction - I've nearly lost a number of fish. Compare this to the risk of bucket changes and a gravel cleaner (that usually has a filter on it). The fish may be partially suctioned but they can't go anywhere.
To get suction you have to attach it to a faucet with the right fittings - in my house that's my kitchen sink (my bathroom sink is just too small) - they don't even make fittings for the (much) safer bathtub faucet. So to get enough suction you have to attach the Python then turn on the water full blast (of course 100% of the water goes down the drain) - this is what produces the suction. So you go back to the tank to clean it and remove water, while without your knowledge your old sink is slowly filling up with water because it can't drain fast enough. You check on it 10 minutes later (at the most) and find about 10 gallons of water all over your kitchen floor. Now if you have new pipes that drain very well you may have no worries but my sink actually drains quite well and it STILL overflowed. So I found myself running back and forth between the tank and kitchen (50 feet each way) to make sure that didn't happen. It sucked (literally).
If they had a connector that worked to hook it to a bathtub where there would be not risk of it overflowing then I would consider trying it out again - but according to our hardware stores in the States there is no such connector and I'd have find some weird type of bathtub faucet to make it work (they couldn't even think of one).
So bottom line - other than moving water really fast it is not particularly the greatest thing to use - besides, I like to spend some time suctioning the gravel in the bottom of my tank - and if I took all the time I needed, the water would be sucked out of the tank before I was done.
Get a good gravel cleaner/suction hose and suction it into the biggest bucket you can carry (for me it's a pathetic 3 gallons) but it's still faster than fussing and stressing with the python. As far as your water issue - I'm not sure I completely understand it but unless you can use water straight from the faucet (where you can get it the right temperature) I see absolutely no advantage of the python over the bucket method. There'd be no point in using buckets of boiled water if you needed say 20-30 gallon - or when you're suctioning, hundreds of gallons of water.
/www.zooplus.co.uk/shop/fish/water_and_plant_care/cleaning_equipment/water_exchange_and_floor_cleaning/102655
