I can't give any specific information since I don't own one. I do know it's a powerful fixture, and I have found most chalices and acan lords are low(er) light corals. Acan Bowerbanki seem to be OK with more light than lords IME.
So my advice would be to be conservative in the begining, and move the intensity up slowly and don't go beyond that elusive tipping point where they'll get too much light. Whatever you choose I would watch them very carefully and be ready to back down on a moment's notice if necessary.
Even Gen 3 LEDs can be hard to set "just right" for low light corals as there are so many factors or moving parts to consider all at once: Height over tank which effects color blending, depth of specimens, placement directly under the fixture or off to the sides, color selection, intensity settings, photoperiod, previous lighting conditions...
My gut reaction is 80% blue is too high in the begining unless the corals
In question have already adapted to that previously and its a known quantity. But I'm really not sure. For now I'd just concentrate on the coral's healthy appearance rather than the best color combo. What kind of lighting did you have previously? You might also want to see if there is a Hydra specific forum as some users may have some good insights. Good luck, those are nice lights.