If your using any irrigation if it has a tiny nozzle beware of plugging and blockage. I tested a drip system and it plugged up fast from particles from coco. I think a larger (1/4"+) feeder and flooding with a digital timer is a safer way to go. He is saying 3 weeks away at a time. Dirt with a light nutrient added that floods every so often would be way safer. KISS it! (Keep It Simple Stupid) is what he truly needs. But also make sure to use a covered and closed water source. Evaporation alone could do you in. And do a simple filter for particles on your drains if you do use a pump setup