Will an electric water pump has slower flow if it must pump through a longer tube?

Question

I am planning a series of ponds, where the first pond (near the source of electricity) has the highest water level, the water flows to the second, lower pond, via a small water fall, and to a third, lowest pond, again via a small water fall. The pump, located in the first pond, has a fountain that sprays into the first pond, but I plan to place an underground pipe to pull water from the third, final pond.

Bird's eye view:
                 ________________________
 __________     /  2nd pond              \
/ 1st pond \    |                        |
|          |    |                        |
|    >o<  <--fountain (pump's output)    |
|     .    |    |                        |
|     .    |    |                        |
|     .    ~~~~~~                        |
|     .    ~~~~~~ <-- waterfall down to  |
|     .    ~~~~~~      2nd pond          |
|     .    ~~~~~~                        |
|     .    |    |                        |
|     .    |    |                        |
\_____.____/    \__________!!!!!!!!!_____/
      .                    !!!!!!!!! <--waterfall down to 3rd
      .          __________!!!!!!!!!____________
      .         /   3rd pond                    \
      .         |                               |
      .         |                               |
      . <--underground PVC pipe                 |
       .        |                               |
        .       |                               |
         .      |                               |
          .     |                               |
            . . . . . . . . . . <--water flows into pump here
                |                               |
                |                               |
                |                               |
                |                               |
                \_______________________________/

The pump is like this:

Water is pumped in through the "Flat Box Filter", then sprays out the fountain at the top. If I were to lengthen the bendy pipe, replacing it with 10-20' of underground PVC to pull water from the third pond, assuming the same width pipe as the bendy tube, would that reduce the power of the pump? Or because it is all submerged anyway and water pressure will equalize, would the pump impellers not have any additional strain?

Answer 1

Theoretically, yes, but practically ,no. Regular 1" PVC will have very little flow restriction compared to the strainer and flex suction tube. Suction restrictions are always more important. And to be certain of no affect of discharge pipe I used about 30 ft of 2" PVC for my pond system . It cost a couple dollars more but nothing in the total cost. PS- pumps don't "pull", they push, and rely on gravity, etc, to produce a "net suction head". at the inlet. And , you don't say what the elevation difference is between the water surface where the pump is and the discharge at the fountainhead. That is by far the most important factor. The pump info should have a table something like 600 g/hr @ 1', 300 g/hr @ 4', 100 g/hr @ 7'. Oops! reread the question; The pump must be in the third/lowest pond to have necessary net positive suction head or flow will be very low to zero.