I just read another thread like many before. “You must QT”
This is not an easy answer and it is in what I like to say, "The Fusion Zone". If you have a brand new tank with dry rock and ASW your fish will get sick even if your brother is Saint Peter. New tanks with new rocks with new ASW used by a Noob will have problems, there is no way around it. Sorry Noobs but thats the way it is. Bacteria need quite a bit of time to do what we pay them for and a Noob does also.
So If I were to start a tank like that, I would fill it up (cycle it very good with something dead but not your cat or the fur will clog the filter) and get some fish. Not $300.00 tangs, coelacanths, manta rays etc. But maybe wrasses, gobies, bleenies, cardinals etc. I would then treat them in copper.
Yes I know, I am totally against medication but this is for a brand new tank with a Noob. 11 or 12 days in the recommended dose of copper then put them in that new tank. Their immunity from the sea would still be intact but the fish will feel under the weather (or under the water as the fish will say) and maybe have an upset stomach like when you drank to much at your first wedding.
If you did that correctly, your fish should not have parasites, or if they do, the parasites will also be under the weather.
You need to get all the dry food, pellets and freeze dried food you have, find your garbage can and throw it in there, don't use it no matter how pretty the angelfish is on the box.
Get LRS frozen Reef Frenzy and some big fresh live clams from a Supermarket or live worms, either black or white, they don't consider race a thing. Even earthworms.
Take the clams and throw them in the freezer. In 2 days open them up and shave off paper thin slices to feed the fish. Your tank is new, there is no bacteria so it may cloud the water a "little".
That is fine and if it is a little, it will clear. If your glass looks like 3 day old wax paper that you wrapped your happy meal in, change a lot of water. Increase circulation no matter what you do.
The cloudyness is just a bacterial bloom which is actually good. The fish may not like it but they have to get over it because if they don't like it, they should have run away from that collector.
The bacteria are floating around looking for a place to call home and start a family so we need this.
If the fish get some spots, I would just hope they get better. If they get a lot of spots I would throw them back in that copper because you didn't monitor that first copper dose well enough. (I told you you will have problems)
After a while when the water clears, the fish seem healthy, you notice some growth like algae, cyano, Godzilla Larvae etc. that is good. Add some more fish using the copper.
In time, maybe 6 months of feeding that food I mentioned, add more fish one at a time with (no copper). Don't worry about a few spots, that is actually good because if you followed this, your fish will be immune.
But if you used dry food pasta or pellets, I will know about it so don't blame me when you have to go on the disease forum saying something like "OMG" I followed that Jiboni Paul B's advice and my fish got so sick I had to call 3 paramedics and they are now being airlifted to the Mayo Clinic for MRIs.
You can continue to use copper for new fish, but I would not advise that because with no parasites, the fish will lose their immunity to them.