I find it hard to believe it is flow as this 10 x thing is relatively new & I grew plants for 20 years with very low flow.
Two main criteria are required ... light & Co2.... everything else we discus like substrate, ferts & water changes are second to light & Co2.
Fitting the atomiser in front of the filter wont increase the amount of Co2 in the water, in fact it wont be as effective as a mist! (might look better though)
Test you PH get a 1.4 drop before light & that will at least prove you have enough Co2 going in, then you only are left with light.
I guess the other option is, Dean is laughing his socks off at all of us & really he has a 6' tank brisling with plants