I'm running a planted+ on my 29g and would agree that the par probably falls a bit below the ray2. I've never tried HC in it but if I were to guess I'd say it might be a little on the weaker side for it, although as already mentioned the co2
and ferts would play a significant role in deciding that. Have you considered Monte Carlo as an alternative to HC? Could be a good option if you go with the planted+ as I had no problem getting it to carpet on both EcoComplete and aquasoil. If your goal is HC though a better option might be to look at an Exocotic e-series (much more powerful and also dimmable, although light distribution is a little acute) or hold out for one the new lights Finnex is supposedly launching in the next few months. You could also experiment with one planted+ and if necessary double up later down the line.
Sent from my iPad using science