Vapo, unfortunately YES. I'm limited to 2 10 gallon tanks. Combined, both hold around 150-200 fish. Monetarily down the line, that represents a lot more than what the Allardi cost me to this point.
I haven't completely GIVEN UP on changing a tank over to QT, but there are several steps in the only scenario I have at my disposal. The first involves moving all the babies from Batch VI (around 40, also 40 days old) to a breeder net. The only tank available to handle a breeder net full of 40 babies happens to be a 24 gallon with 16 fish in it already. So there's my first hesitation.
IF I were to move them out, the next step is to move all the babies from Batch VIII, which are currently only 15 or so days, down into the lower 10 with the Greenbanded Gobies (which are currently sharing quarters with Batch VI). This then opens up an empty 10 gallon tank.
These 2 steps have been in my mind since long before the Seahorse/Allardi/BlackOC/Mandarin#1 tank broke out with ICH. It was a tentative plan for freeing up the top 10 gallon tank to try to rais another batch of whatevers...whether that be another Perc Batch, or more likely another attempt at Apogon leptacanthus.
IF I were to implement this series of moves, that still leaves me with an empty 10 gallon tank with no seeded biological filtration, and that's a problem I have no quick or easy solution for at the moment. If I were to move the fish, the question at this point is whether I move only those showing symptoms, or move them all. To move them all is to move 2 Allardi, 2 Barbouri Seahorses, 2 Mandarins, 2 Rusty Gobies and 2 Black Ocellaris all into a 10 gallon tank with NO seeded biological filtration. And to be truly effective as a long term solution, this means leaving the fish in this 10 gallon tank for a minimum of 30 days, but 60 being more ideal.
So in weighing out all my options, I see a couple issues. First, copper as a medication is out ANYWAY due to the possibility of delaying or sterilizing broodstock. 2nd, the increased stress of the move may cause fish that are currently unaffected to break down. Third, having no established biological filtration means that while the fish go through quarantine, I'll have to deal with a cycling tank.
I may have mentioned this before, but I did have a somewhat simliar outbreak in the cardinalfish tank a while back when I stupidly introduced a mandarin that was covered in ICH (simply didn't bother to observe the fish in detail when I had the guys at the shop bag it up...since they know my background, they didn't bother to check the fish I had selected either, can't blame 'em). Anyway, the ICH spread to other tankmates largely due to my UV not being running. I implemented the same initial "treatments" I've used on this current outbreak, focusing on heavy water changes and probiotics, and overall it worked out in the end, no losses. However, none of the fish got nearly as bad, nor as quickly, as this current problem has.
The fact that this cropped up without ANY new additions has be boggled...the tank hasn't gotten a new fish in MONTHS. According to the prevailing "data", ICH isn't supposed to be able to just "crop up" out of nowhere, and isn't "brought on by stress", but unless I'm overlooking something, this is EXACLTY what has happened in my tank.
For now, I'm doing what can be done I suppose, given my current situation. Unfortunately, a THIRD 10 gallon tank literally is not an option..there's literally no place to put one. So that means, based on the reasoning above, that I'm going to have to leave the fish be in the reef setup, and I'm going to have to do everything I can within the constraints of a reef setup to rectify the problem. Trust me, I literally thought about using something NOT reef safe - other than a nice cup coral and the 2 rhodactis, the rest of the coral / invert life in that tank is "replaceable". I also thought about MOVING that life out, but of course that really increases the risk of introducing the ICH into a 2nd tank (which is a worse option). So, they're stuck in the reef for now, and I'm hoping that with all my good efforts the fish can turn the corner on the ICH.
FWIW,
Matt