We just installed this yesterday, thinking we could run water to the bog filter and waterfall at the same time. But try as we will, it seems to only run to one outlet at a time. Is there a trick to operating this? Or did I buy something that doesn't work the way I thought? Here's the link: https://www.amazon.com/OASE-Y-Distributor-1-2-Inch/dp/B00I81EBJ4, any help would be much appreciated.