Long tubes

[gr81]

Hi,
I use small pump (max. 300L/h)in a tank. If I plug long tube witch will lead approx 10m under tank and then back to tank (under water line). Will this cause a pressure lost?
Why I want do to that: I have cellar udder room where temperature is approx 10
°C whole year, so I want to cool a little my tank this way.

[NanoDave]

There will be pressure lost not due to the height, but due to having to push through 10m of tube. If the inlet and the outlet is the same height, it will push at the same rate as if the tube is laid completely horizontal. :)