Fish how is it done ? HELP!!!

I'm not running in after RRP's mayonnaise kick but it is used classically as a stick preventative for grilled fish. Sea bass is great grilled hot and fast with no smoke.

Lots of ways but, I personally prefer CI pan blackened. And with some mango salsa or pineapple salsa.
Or you could just scale them and go straight on the grid if that's your thing.
I'm familiar w/ Sea Bass but, "Black Fish"?

I fish and catch both often.
Seabass Cooking the fish whole, I put EVOO on it, score the skin shallow and season with some thyme, salt and pepper under the roaster on low. flip when the skin gets crispy- 5-7 mins. When roasting, put on a cookie rack, and you should be able to keep the side that is down from getting soggy.
On the egg, you could probably do the same thing, raised direct at about 375.
I have a new way for Blackfish, AKA Tautog... and do not knock it till you try it... 2-3 cups of water with 4 tablespoons of brown sugar added. Cut up the tog/blackfish to one inch cubes. Boil in water/brown sugar mixture for about 2 mins. Take the larger pieces, and cut one in half in half. If white all the way through, it is done. Once done, strain and rinse with cool water for about 20-30 seconds to stop cooking. Dip in clarified butter and add old bay if you like it - you ill think it is dungeness crab. Personally, I do all steps, cool longer under the cold water to it is cool to the touch then I toss in a little clarified butter, and sprinkle on top of a dressed salad with a very light dusting of old bay.
Or you can blacken either one.
I know.... cook something but not on the egg? GASP!!! But that is how I like to cook these tasty fish best. Blackening is great, but you do not taste the fish itself. Usually just the seasoning. If you are getting really fresh fish, try these methods just once. I do not think you will be sorry.

I use a disposable expanded aluminum tray. Spray with it Pam. Season to taste. I grill raised direct, flesh side down for a few minutes to add grill marks and color. Flip to skin side down while fish is still firm. Remove when fish flakes easily and when it turns from translucent to opaque. Approximately cook time is 10 minutes per inch at 400°. When I'm ready to remove the fish from the grill, I gently slide a spatula between the meat and skin. This allows you to plate just the meat without the skin. I then toss the skin to the cat or dogs.

There is also a product out there that is great for fish. Frogmats.

I don't know what black fish are but blackening will overpower the sea bass. I would do a light mayonnaise coating and grill at 400*. Sea bass is real expensive here and I wouldn't waste it. I'm not talking about Pantagonian toothfish either.