submersable pump to circulate water

[bribri]

Is it a reasonable idea to put a small submersible pump to circulate water from bottom of pool to top. The pool is not opened yet and the solar cover is on. I noticed that the surface temp during sunny day to be 50 degree but only 40 degree 4 foot down. Would the pump increase the solar heating from the solar cover.Or is this a waste of time money and electricity. I may also use the pump to run water through 2oo ft of garden hose.
Thanks, Brian

 

[JasonLion]

You will get more heat that way, though it won't be all that much more hear and it won't be especially efficient. The long garden hose approach is particularly inefficient.