Fountain Water Supply

I built a custom fountain. The water splashes, so I installed a water supply for make-up water. I ran almost 50' of 1/2" ID reinforced tubing from the house supply and installed a float valve in the sump to maintain the water level.
It's been working great.
Recently, I bumped into the specs on the float valve. It says the max pressure is 10kg, which translates into 22psi.
The house pressure feeding it is about 65psi.
Even though it's working, I'm concerned about the pressure causing the float valve to fail. Does the 50' run of tubing drop the pressure at the valve? If not, can I install a pressure reducing valve, adjust it to 20lbs, and still have the float valve work properly 50' away?
Thanks in advance

No it will not drop the pressure.

What about the second question?

can I install a pressure reducing valve, adjust it to 20lbs, and still have the float valve work properly 50' away?[/I]

Sounds like a cross connection to me.

Float valve will still open and close if you drop the pressure with a reducing valve. 50 ft will not effect the flow that much. The volume you require will depend on how much water is lost through evaporation and leakage.
how may gallons of water will it require per recharge. 5 or 100.
some swimming pools was a small sump with a Fluidmaster toilet tank fill valve to maintain the water level. those will work at you current water pressure and they are inexpensive.

Or just get a better fill valve. reducing valve will cost maybe as much or more than just upgrading the fill valve