I have a 8x8x8 Grow Tent that I will be flowering in. Using 2 4x8 tray's each with a 70 gallon res. My question is, does anyone have any good suggestions on how to construct something to support my trays over the res. I've always used cinderblocks in the past but this is my first hydro grow and the cinderblocks down't leave enough room to slide the tray in and out easily. Any help would be greatly appreciated!