I'm trying to grow vertically using a low power setup, my current design has to move the water up to around 5-6'. I'm planning on using NT rather than the planned ebb & flow, then using a number of tiers to fill vertical space with greenery. I'm struggling a bit with pump choice.

Is there a simple way of estimating flow with different head lengths? Does anyone have experience of a very low power pump that has a suitable head rating? Efficiency is important.

Currently there's no FT, although the aim is to introduce aquaponics to it. I can get away with far less flow to experiment with the rig without fish.

Thanks.