Let me compile it here Rc won't let me edit missspellls from months ago lol threads lock in an hour. Ur right a summary is in order, not just of this thread but all the ones I peruse online to check for consistency. I'm at work so this will be in pieces:
Modes of application
External spot treatment, safe across all tanks as no peroxide gets back into tank
Remove target rock, apply to target only, wait two mins, rinse and reinstall
Target applications that wet benthic organisms such as pods and brittle stars that happen to be in the area may kill them. It won't affect the rest of the ones in the tank.
Whole rock/frag dip
For corals known tolerant, some people dip the whole frag/rock in a solution of half 3% peroxide half clean saltwater for a few mins, rinse, reinstall and this is very common
Emersed spot treatment, in tank: this begins methods that introduce peroxide into the tank. Its exclusively what I use and my videos show. Its popular because you leave things in place, you just drain water down to desired access level. Methods that input peroxide into tank assume you checked off your stocking list against a list of known sensitives. Most reef organisms are very tolerant of a little peroxide.
Whole tank dosing/1:10 dosing and submerged spot treatment are ran with a tank full of water. The easiest method involves the least work, its been used on giant tanks here, but contacts everything in the tank with peroxide so you have to be mindful of what's in the tank. 1ml per ten gallons dosed 3x times a week has never been shown to affect pods, benthic life or filter bacteria
I've read of people using 3 and 4mls per ten with faster kill and no collateral loss. I recommend 1:10 as a safe zone with decent efficacy.
How fast it works on the actual target ranges based on target...red brush algae might not be affected at all in this dilution...but bryopsis and gha and cyano and diatoms show excellent susceptibility to it in these doses after a while
The submerged spot treatment injects peroxide onto an underwater target just for that brief contact time, it kills targets faster than directly dosing a tank, systemic dosing.