RTN out of nowhere

[Sierra_Bravo]

My first experience with RTN: My Tri-Color Plana frag was fine this evening after work; tonight I'm doing a routine check and the top third is sloughed off and blowing in the current. Everything else looks fine. I didn't see any pest, but performd a dip and cut off the section that had tissue necrosis. I guess I'll see what it looks like in the morning. I'll post parameters below. .. if you have any thoughts on what causes this type of event let me know.

I was just thinking earlier today how happy I was that things were really staying stable and looking good. Very frustrating.

Parameters:

Temp 78
Salinity 1.025
pH 7.98
Alk 8.6
Calc 405
Mag 1320
Nitrate 2
Nitrite 0
Phosphate .052

 

[Ocelaris]

Calcium is a bit low, but with a random patch gone, may be a disease. I'd hack off the bad, back to the good section and wait. Maybe feed them with reef chili or the likes. Anybody else look stressed around there? What's the normal dosing cycle look like?

 

[Som1else]

I would cut the bad part pretty well below that damaged section to try to save it. Ive had whole colonies half rtn during a single day. It doesn't happen often but it can happen and has to me more than a few times. I always cut multiple frags as far away from the affected area as possible and so far i have been able to regrow them.

 

[Ocelaris]

Yup, that, disease means cut and start over, not necessarily anything you're doing. Now if more rtn, then you might have nutrient issues, but one off, cut off past healthy tissue and sterilize that tool.

 

[Sierra_Bravo]

I chopped it at the halfway point of the frag. After dipping I set on a separate frag rack a little lower. We'll wait and see. I've been reading posts about RTN with this being my first experience and I guess I'm in good company with regards to people that have dealt with it. Thanks for the tip about sterilizing the bonecutter - I would not have thought to do that.

 

[Sierra_Bravo]

Calcium is a bit low, but with a random patch gone, may be a disease. I'd hack off the bad, back to the good section and wait. Maybe feed them with reef chili or the likes. Anybody else look stressed around there? What's the normal dosing cycle look like?

Dosing is basic two part on dosing pumps controlled by a Reefkeeper. Stays in the 8.5 - 8.7 range between weekly water changes. Calk has been harder to dial in but has never been lower than 385 or higher than 430. Tends to stay around 400 - 410.
Nothing else stressed but me.

 

[Sierra_Bravo]

Checking this morning I don't see any further sloughing of tissue on what's left of the frag. I guess I'll cross my fingers and see how it does when I return from work tonight.

 

[cobra2326]

Calcium is a bit low

I’m sorry man, but posts like this saying “x number is slightly off” just aren’t helpful. Balanced calcium at 8.6dkh alkalinity is 422ppm. That’s within the error range of most test kits. Even if it were 350, it’s highly unlikely to be the cause of his RTN. Again, I’m sorry for singling you out, I just see this way too much and it gets people off chasing ghosts that are very unlikely the problem.

 

[BigJim]

Did you make any changes to your powerheads? I have had this happen when I changed flow pattern and a coral was getting too much direct flow.

 

[Sierra_Bravo]

Did you make any changes to your powerheads? I have had this happen when I changed flow pattern and a coral was getting too much direct flow.

No. I have Maxspect Gyres and they've been in the same position with the same flow patterns.

 

[Sierra_Bravo]

Well, unfortunately the tri-color didn't make it after the clip and is nothing but white skeleton this morning. The bright side is that I have one more space in my frag rack to get another frag, I guess. . .

 

[Som1else]

Just keep moving forward. Once you've been doing this for a long time its just part of the hobby.

 

[Guttersnipe]

Just keep moving forward. Once you've been doing this for a long time its just part of the hobby.

This is so true.

 

[Waters]

Your first problem was thinking that everything is going good....that is usually what triggers problems for me lol. I have had off and on issues with RTN over the last year and traced it (I think) to nutrient swings. Has everything been stable (Alk, Ca, SG, nitrates, phosphates, temp)? Did it happen after changing GFO or Carbon?