I got one of those Eco air pumps, 38 Liters per min. The commercial one that the guy at the hydro store said would do all the dwc totes I needed. Well now that I started a second DWC tote it doesn't push barley any bubbles out of the two air stones in the new tote. I hooked up a splitter on the main pump running two hoses....one to each tote and split to two air stones in each tote. When I took one hose off the pump the other one ran great and did the same test on the other tote and it ran great. So basically I only get one tote/2 air stones out of the pump. Does any one else run the same pump on more than one tote/bucket?