first off, its recommended you get yourself a different airpump than the one that comes with the waterfarm. You can go to Walmart or similar and get yourself an aquarium pump rated for up to 50 gallons.. they are like 10 bucks..hey kriznarf just a quick question how long do you run your airpump iv just bought an aquafarm and i'm abit wary about how many times a day do you run yor airpump and for how long thanks in advance
As for for when you should run the pump.... You do NOT turn your pump off as its basically breathing for your plants roots and it doesn't take long for those roots to get damaged when the pump is off.. hope this helps
edit:
I just saw you posted that you bought an aquafarm.. i do not know what kind of pump they come with but i'll leave my original recommendation just in case..