Hi, I'm having issues with my system. I've built an auqaponics system using a converted IBC tank. I've got a little low power consumption pump which fills the tank in just over 15 minutes. I'm happy with that at this stage as the grow bed is empty of media. My syphin starts at the required height also, however when it reaches the hole drilled at the bottom of the bell syphin to let air in, the wa…