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

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?

• You might want to consider keeping the short flexible tube untouched and cutting and extending the pump output port instead. Jun 28, 2020 at 15:14
• Adding length increases the pressure drop. Jun 28, 2020 at 15:24
• What is "pressure drop"? Jun 28, 2020 at 16:09