Water Tank Plumbing for a Solar Pump

Can I make a long horizontal run to a distant storage tank?

Yes, this is not a problem and has minimal impact on head/flow rates as long as the diameter of pipe is chosen properly to prevent significant loss of pressure (pressure drop) over the run. Our customers routinely make 1 mile horizontal runs. Ask an engineer if you are unsure about a longer distance but generally we recommend 1″ for distances under 1000′ and under 5 GPM. Frictional losses go up as flow rates and distances increase.