will this work to change water?

It could. You just need to know for sure how high you need to pump water. And have a pump that will do that. Is everywhere Up where you're at?
 
so you're just trying to speed it up a little on the down hill run right? I don't see any problem with that. Ok, you mentioned pumping back to the tank. Is the water coming from the toilet to the tank?
 
no from the bath tub or sink. all im trying to do is to make it to where i dont have to carry buckets bc im unable to for a couple of weeks.
 
OK... so I'm guessing you don't have a python. Do you already have the hose to do this? I'm guessing the run FROM the tank won't be sped up much. Because at 200gph, that's only 3.3 gallons per minute. Now on the return. Coming from the bath tub will be slower than the sink. Because it will have to push the water approx. 4 ft up. Compared to 1 to 2 ft up from the sink. This is where you need to know the specifics about the pump. A 200gph pump might only pump 100 gph 2 feet up and 50 gph 4 ft up. Some are made more for Flow(almost lvl movement, like a power head in a tank) and some for Pressure that are good for pumping Up for fountains and stuff.
 
You have a sink, and a down hill run. Why not just invest in a python or similar product? Makes wc's soooooo easy.
 
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