I am upgrading my two Hydra 26 HD's over my reefer 350 in a 4bulb T5 hybrid fixture with two Radion XR15 G5 blues, and will be getting a 3rd xr15 next week as well. What would be the best way to make the switch without a PAR meter? Should I just try to match the total wattage output? I'd appreciate any advice
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