160ppm nitrate suggestions?

[FitoPharmer]

I also had a question about denitrate from seachem. In my google search for nitrate reactors I came across this stuffed into cansiters or media reactors and suggested a low flow rate of 50-60gph. It reminded me that this tank has a layer across the sump floor. Is this stuff effective when it is used at the right flow rate? or should it be removed in favor of other equipment? Some how I doubt it is getting the right flow right now. The top gets too much flow and underneath gets little to no flow and traps detritus.