No diffusers.Thanks. If I remember correctly that’s with no diffusers right? I have my radions mounted 16” above the water and only get 380ish at the top of my rock which is 8” below the surface. Seems low to me with 3 radions over a 5’x2’x2’ tank.
Your par sounds about right to me also. On my frag tanks (48”x24”x10”) I used the aquatic life t5’s and 3 Radion xr15’s and my par would be 350 for the high.
380 par is more than enough imo. I like to be between 250-400 par.