Nevermind, I bought an SQ-520 and it works great!! I got the 520 so I could measure full spectrum.
PAR at the bottom is ~64 at the top is ~290-320 so a little high, but I am swapping out a few of my white LEDs with 450nm blue. Once I do that, I'll use the PAR meter and adjust lighting so that at the peak, the PAR is 50 at the sand bed.