Reef - Ich - Organicure - Fallow Tank - Aaaaargh ! ? ! ? ! ?

[VFX]

After running my reef for a year without any signs of ich, I did a little bit of aquascaping & disturbed the sand bed. I always QT everything before it goes in my tank. Well, everything except for the LR which I've picked up from 5 fellow reefers & 2 different LFS.

Anyway a few hours after I finished, my fish got ich

I removed everyone & put them in my QT tank & started treating it with some Organicure & a week or so later signs of ich are virtually gone from the fish.

How long do I need to leave my reef tank fallow for to make sure the Ich dies off completely? I've read & heard anything from 6 to 12 weeks.

Not a problem normally but I don't really want to keep butterfly fish in a 10g QT tank for 12 weeks!

I have set up a 15g for my frogfish but I'm guessing that has ich too as the LR & sand was from my reef.

Organicure says it's safe for fish, crabs & shrimp. Should I risk using it in my reef or in my frogfish tank (contains some LPS, gorgs & clams)?

It also says it contains 1.25% copper & 17% formaldehyde, so it'll probably kill my corals, clams, pods, worms, starfish etc. ?

Oh & to anyone running UV. This is a good example of it being useless against ich that's not already in the water column.

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