Need some advice

[Fallling]

So, I'm kind of at loss now, but here's the story.

I had 3 ora yellow assessors and juvenile marine betta in QT since 7/8. My 125 gal DT has been fallow since 8/4 as I determined at least one fish was infected with flukes and internal parasites. Note that my that the DT hasn't had any new fish in over a year. All fish are in QT and have gone 2x rounds prazi at 7 days apart for flukes and along with 14 days of feeding metroplex/focus/garlic soaked food (including the assessors/betta as I had to temporarily put a DT fish in their quarantine- I know, not great, but I won't get into the why of the matter here). As of 9/22, the assessors/betta have been in QT for about 11 weeks- I never saw any signs of disease/spots/flashing/flicking/etc. Since the fish were in QT for so long, I decided to forego copper. None of the DT fish (currently still in QT) have ever displayed any signs of ich.

I added the assessors to the DT on 9/22, about 11 weeks after quarantine. 9/24, the betta went in. I came home from work yesterday and 2 of the assessors had white nodules on the edges of their fins. UGH. They also had some small grayish spots/patches on the body. This morning, the white nodules appear to be gone. I've never had ich in my DT- I was thinking maybe it's actually Lymphocystis but can Lymphocystis disappear over night? I know ich falls off as part of the cycle, so that makes me inclined to say it's ich. However, I can't believe I didn't catch any sign of it in QT over 11 weeks. Only 2 of the 3 assessors showed any signs.

At this point, I'm sure the right approach is get them all out of the DT and start the process all over. However, I have yet to see the marine betta come out of hiding which means tearing the tank apart to get at it. Does it seem like ich over Lymphocystis (or something else)? Any advice is appreciated. So frustrating and disheartening. Ugh.

I tried to get some pics:

Circles on the body are flat, gray patches. Circles on the fins are white nodules.

Same as above without the circles for reference.

Below aren't my fish but 2 pics I found that look pretty similar to how to white nodules appeared along the fins.

 

[GHsaltie]

The spots on the fins I can't decide if they look like ich or lympho, however ich wouldnt pop up and disappear like that in a day unless the parasites had already been feeding and the fish didn't show any signs of it. When was it that you put the other fish in their QT? The grey patches sound and look bacteria to me. All of this is conjecture though so I'll call in some others that will hopefully figure it out.
@Humblefish @melypr1985 @ngoodermuth @aykwm

 

[Humblefish]

The good news is if it came & went in 24-48 hrs, then it can't be a parasite. White nodules staying only on the fins/spines highly suggests Lympho. Those can come & go in short order, especially if you happen to have a cleaner shrimp in the tank.

 

[ngoodermuth]

The spots on the fins look like lymph to me. While lymph can present on the body as well, like @GHsaltie mentioned, it could be bacterial...so I would just keep a close eye on it and maybe add some vitamins/selcon to their food for good measure.

 

[Fallling]

The spots on the fins I can't decide if they look like ich or lympho, however ich wouldnt pop up and disappear like that in a day unless the parasites had already been feeding and the fish didn't show any signs of it. When was it that you put the other fish in their QT? The grey patches sound and look bacteria to me.

Thanks for the input. The other fish was in their QT back in July for a few days. It does seem to be something bacterial going on with gray patches- I don't think I'm as worried about it being ich since the white spots were just along the fins/spine and appeared/disappeared so quickly (not a 100% ruled out, but seems more likely it's something else). The fish are eating/acting ok, and it's not getting worse (seems to be getting better- they actually look fine in diffuse natural sunlight this morning), so I'm going to keep an eye on them for now. They get do get a wide variety of selcon soaked food (mysis/cylops/calanus/rotifers, oyster eggs/etc- there's a lot of nps in the tank that needs different sized food).

I have a 40w Emperor Aquatics (I guess it's Pentair now) UV sterilizer that I'm going to hook back up on the closed loop this weekend as well. I never hooked it back up when I moved to a new residence 3 years ago- It might help with bacteria in the water column. A the very least, it certainly won't hurt and does make for crystal clear water = )