Unknown Frog/hammer pest, microscopic ID help

[Felipe BDG]

Recently I did some changes on my tank. I sold lots of colonies and kept only some frags because I did a layout change. I changed all my rocks and switched from a calcium reactor +2parts to 2-part dosing only. I had some parameter fluctuations, so I was expecting losses.
I have stable parameters now and was expecting my corals to start thriving again. The thing is, my SPS and soft corals are amazing, growing really well and even better than before, but the frogs and hammers…
The Duncans are fine, torches too, but frogspawns and hammers are dying. Some big-polyp Blastomussa too. I thought they were still adapting, but they kept dying. I lost almost all hammer species and the frogspawns are in bad shape, some better than others.
I decided to do some investigation with a microscope. The thing is, I found this weird unknown pest on all the frogspawns and hammers, in large numbers. There were some on the Blastomussa too, but almost none on torches, Duncans or other LPS.
So, does anyone know what this is?
they swim FAST! I will include some pictures of the corals too. Some had BJ, but almost all of them just started shrinking, losing tissue, and then died without brown jelly.

 

[Felipe BDG]

I couldnt get kcl, but i did dip with milbemicine, levaemisole, redsea and seachem... no visible changes to the coral, microscopy post dip show less of the unidentified thing, but they could have just swum out of it... I got some samples from the affected corals with some tissue, and they were all over it (the blobs on the video is coral tissues/ coral mucus)

 

[mcarroll]

Assuming a microbe is a pest is the wrong foot to start on.

There's no reason to assume the paramater fluctuations you experienced aren't the cause of these problems. (And that is far from the only stress your corals underwent through the system change.) Symptoms don't always show up right away, and sometimes recovery isn't complete even when environmental conditions improve. Maintaining positive N&P numbers will help. ≥0.05 ppm PO4 and ≥5 ppm NO3 is where I'd start. Higher numbers would be OK too.

BTW, "brown Jelly" is a symptom, not a thing in its own right, let alone a "disease" as others are trying (very hard) to portray it.....just a byproduct of necrosis when there's a lot of tissue (eg "LPS") going at once. Same happens on other corals when they "STN/RTN", but the tissue is so thin/minimal (eg Acro's and other "SPS") that it isn't noticeable the same ways. Whichever name you call it, it's usually related to parameter swings (and the resultant negative impact on photosynthesis), but any "cause of death" will do....that's what necrosis is for! :)

 

[Felipe BDG]

The Little critter could be just taking opportunity on dying tissue, but I don't really can find any other cause so specific for the frogs and hammers, parameters could really be the issues as a late symptoms of the change I gone through, but all the other corals are fine, even the torchs that are so similar to them... I had some calcium and alkalinity instability (I used to keep it on 9, it fell to 7 and since this I've kept it around 8, phosphates are 0.22 on Hanna and nitrates is 5 (nutrients haven't really fluctuated, I test weekly) I've been slowly elevating my magnesium, as it was 1170 with the reactor and now it's 1260 ppm, the layout change was some months ago (around august) and the aquarium has been pretty stable since around late October. I forgot to send the coral pictures, i think interesting that it Didn't just BJellied, the coral spent some weeks shrunken (not closed but not stretching as it was supposed) and then just start losing tissue, and started looking really bad... I had bj before and it would just melt over the night, this is different somehow, looks like the coral is somehow trying to kickaround untill the stressing factor gets too overwhelming... I used to have colonies close to 100 heads of all these corals, I've kept the frags and now they are just terrible, someone gave me 2 new hammers late november and things started to get worse after this

 

[mcarroll]

Well, parameter changes may have actually been the least of the stresses they encountered through the changes. Mature colonies do not generally handle changes well IME. Changes in lighting and flow can be very detrimental....I've had whole colonies RTN from a simple change in flow. Also consider that flow has a unique impct on each coral because flow is not homogenous throughout the tank. Light is similar in it's unevenness through the tank. So it's possible that the variability you're seeing in results is just because of these differences. To wit, it's possible to have the same coral in two places where one is RTN and the other is happy. Same tank, but different living conditions.

I wish you could have more certainty about what is going on, but a pretty complex set of changes has happened (very fast), so things could very well remain unclear. You could even consider this an unusual case of New Tank Syndrome, IMO. Consider that you don't have an old tank, redone. You have a new tank with some classic frags in it. :)

BTW, could you post your vids elsewhere and link them here? I can't actually see anything but the pic. Someone might still ID your critter.

 

[Felipe BDG]

Oh, flow definitely changed after fragging the colonies! I guess this is some of that times when you only can have patience... Sorry about the video, I will upload it on youtube, I didn't realized they uploaded as pics

 

[Felipe BDG]

 

[mcarroll]

Very cool videos – great footage! IMO it's some kind of decomposer at work, but that's a barely-educated guess.

Hopefully someone will be able to ID!