[![Pressures.][1]][1]

The *static* pressure $p$ depends solely on the height $h$. If $p_0$ is the atmospheric pressure, then:

$$p=p_0+\rho gh$$

Where $\rho$ is the liquid's density and $g\approx10\:\mathrm{ms^{-2}}$.

So for the left hand side tank the pressure would be slightly higher because the tank is taller (not because it has higher or lower capacity).

Flow through the pipe always causes some viscous pressure loss though.
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**Answering OP's concern (comment section):**

> Do I need a tank and secondly as far as I can gather from you guys it is the pressure that the water leaves the bottom of the tank is the pressure at the end of the pipe?

If you have easy access to the stream, a tank is not required.

The pressure discussed in my answer is called *hydrostatic pressure* and for good reason: if one **blocks** the end of the pipe, the pressure $p$ at that point would be *exactly* as indicated ($p=p_0+\rho gh$, where $h$ is the *height* difference between the water's open surface and the pipe's end).

But when flow is allowed a certain amount of pressure is lost due to friction in the pipe. In that case the *corrected* pressure can be noted as:

$$p'=p_0+\rho gh-\Delta p$$
Without going into full details of *pipe flow theory* we can say with certainty that $\Delta p$:

 1. *increases* with pipe length,
 2. *decreases* with pipe diameter,
 3. *increases* with volumetric throughput (flow speed),
 4. *increases* with pipe inside roughness: smooth, uncorroded, new pipes reduce pressure less,
 5. *increases* in the presence of local resistances like bends, kinks, valves, sudden diameter changes and such like.

A short, wide, smooth, straight pipe operated at low flow speed will deliver pressure almost identical to the hydrostatic pressure $p$.

But using a long, narrow (etc) pipe can lead to *almost all* of the hydrostatic pressure being lost to friction ($\Delta p \approx p_0+\rho gh$).

[Further reading: Darcy-Weisbach.][2]


  [1]: https://i.sstatic.net/A6Nar.png
  [2]: https://en.wikipedia.org/wiki/Darcy%E2%80%93Weisbach_equation