That's 2.56 watts per gallon which is quite a lot in the led
world especially if the tank is only 24" deep or less.
For example, my system is mostly stoney corals and the 300 gallon tank is 32" deep. I light it with about 400 watts of led
with lenses (to accommodate depth). That's about 1.3 watts per gallon. That replaced 1400 watts of MH
/actinic which was 4.66 watts per gallon. I think X is right, you may have underestimated the actual PAR the led
A lot of folks end up buying dimmable panels and many times end up operating them at 50-75% power.
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