Version 1.1 - 'Optimise'

The plan was to remove the weakest link, the guttering.  I bought garden irrigation pipe used for hanging baskets so that the water from the pump would drip feed into each trough individually rather than gushing into each trough.  I soon found that this method works only due to mains water pressure, a small pump just can't create the necessary water pressure.

I abandoned that idea and instead used normal hosepipe linking the pump to trough number one, with connecting water pipes connecting subsequent troughs back into the reservoir, a bit like an overflow. This seemed such a simple idea I couldn't understand why after googling it I couldn't find anyone else who had done it (there is a reason!)

Lessons learned

1. It was a nightmare to connect the troughs and pipes together especially as they are beneath the ground.  Getting one end in inevitably meant another pipe came out.  Even when using lots of silicon sealant I couldn't get a watertight seal which meant lots of expensive hydroponics solution was continually lost.
2. Alas I didn't think about the reservoir size I actually needed so I just bought a food grade 25 litre container.  This an important point ensuring you have enough nutrients for the plants.
3. Having ten flower troughs meant I needed over 90 litres of clay pebbles which not only added to the cost but also had an impact on the amount of nutrients needed (and ultimately the reservoir size).

Shopping list

1. Canna 45L AquaClay Bag from @ £15.99 each Amazon
2. 46m Micro Irrigation Watering Kit @ £12.77 Amazon
3. VivReal 12V DC Submersible Water Pump @ £12 Amazon