Destroyers or Opportunists?

[Cook]

I've been losing SPS for a while. Never more than one at a time. Generally, it's slow tissue loss from the bottom up. Parameters are reasonable. I haven't been able to find anything on a frag until last night. I have a microscope at work, so I'll get better pictures tonight. Let me know what everyone thinks. This is in my frag tank, and I'm not selling anything out of it until I can figure out what the problem is and resolve it.

 

[Phil]

They don’t look nice. Lol. Sorry nan

 

[civics14]

Hard to say, looks like amphipods to me. I know several people have been dealing with issues this past year with SPS with no signs of pest, including myself. I'm beginning to think its bacteria related or some form of pest that can survive extreme dips.

 

[hzheng33]

Good for you and thank you for making that decision of not selling until you find out what’s going on.

I agree with victor, I don’t see anything out of the ordinary....yet

have you checked and validated your salinity? Last year I was going through some Stn and it was because my refractometer was not accurate causing my salinity to be 30ppt

 

[Rainblood]

Same here. My refractometer required constant calibration - my salinity ended up being low as well.
Now I just stick with a cheap old hydrometer.

 

[spike]

look for acro eating flatworms that tend to attack the coral as you are noting. They lay eggs on the white coral at base and attack the underside of the acro.

 

[gainesvillereef]

A lot of times we blame the clean-up crew for tissue necrosis. I have always found that STN and RTN are related to starvation. Low phosphates in particular. But this past year I found a counterintuitive cause as well. I was having the same issue with my new tank. Bottom-up STN. I finally got the clue from a Dana Riddle video. Apparently, the Zooxanthellae will stop photosynthesis above a certain level of par. But the worst part is that the effect is sometimes irreversible. So too much light can cause starvation as well. I was at my end so I turned down my lights and I have not had any more necrosis in the last month. Also, the still surviving corals with some STN have healed up. Here is Dana's video.

Turbocharge Photosynthesis! Alkalinity, Light, & Water Motion by Dana Riddle | MACNA 2016

I can't prove this, because I don't have a spectrometer, but based on what I observed the blue spectrum is both the most important to photosynthesis in coral but also what the coral limits (often referred to as coral PUR). I had added supplemental blue strip lights because I thought they were needed by my high mounting (20") of my lights. Turns out they were not needed and I had to turn them way down. Basically, I turned off the strip lights and went solely with my Kessils. The strip lights were adding about 60 PAR by themselves at 20%, but all blue. With the strips on, I was reading about 250 PAR at the frag rack deck. Without them, I now read 190. And my STN problems have gone away.

If you use a broad-spectrum light like a metal halide, probably less than 30-40% of the PAR is PUR. With Kessil tuna blues the PUR probably makes up 60-70% of the PAR. With the actinic strips, it's 100%. So doing the math, without the actinic strips, my kessils at 190 PAR were roughly equal to metal halide at 350 PAR in terms of PUR. With the actinic strips, my corals were getting the equivalent of 500 PAR with metal halide. Based on Dana's video, I believe that was causing photosynthesis to shut down and starved the corals.

​

 

[Eric_n_Ga]

I'm dealing with same scenario, did notice it until I kept tweeking my lights up.

 

[NanCrab]

A lot of times we blame the clean-up crew for tissue necrosis. I have always found that STN and RTN are related to starvation. Low phosphates in particular. But this past year I found a counterintuitive cause as well. I was having the same issue with my new tank. Bottom-up STN. I finally got the clue from a Dana Riddle video. Apparently, the Zooxanthellae will stop photosynthesis above a certain level of par. But the worst part is that the effect is sometimes irreversible. So too much light can cause starvation as well. I was at my end so I turned down my lights and I have not had any more necrosis in the last month. Also, the still surviving corals with some STN have healed up. Here is Dana's video.

Turbocharge Photosynthesis! Alkalinity, Light, & Water Motion by Dana Riddle | MACNA 2016

I can't prove this, because I don't have a spectrometer, but based on what I observed the blue spectrum is both the most important to photosynthesis in coral but also what the coral limits (often referred to as coral PUR). I had added supplemental blue strip lights because I thought they were needed by my high mounting (20") of my lights. Turns out they were not needed and I had to turn them way down. Basically, I turned off the strip lights and went solely with my Kessils. The strip lights were adding about 60 PAR by themselves at 20%, but all blue. With the strips on, I was reading about 250 PAR at the frag rack deck. Without them, I now read 190. And my STN problems have gone away.

If you use a broad-spectrum light like a metal halide, probably less than 30-40% of the PAR is PUR. With Kessil tuna blues the PUR probably makes up 60-70% of the PAR. With the actinic strips, it's 100%. So doing the math, without the actinic strips, my kessils at 190 PAR were roughly equal to metal halide at 350 PAR in terms of PUR. With the actinic strips, my corals were getting the equivalent of 500 PAR with metal halide. Based on Dana's video, I believe that was causing photosynthesis to shut down and starved the corals.

​

Thank you for the link, we’ve been having a really difficult time with STN as well and have all but given up on keeping them

 

[Cook]

I'll address a couple of the comments at once. Thanks for the suggestions and observations, truly appreciated. I haven't calibrated my refractometer, but I do have calibration liquid and I will check it. My salt is mixed in 30 gallon batches and is used for both my display and frag tank. For the amount of salt I'm adding it seems accurate, but verification is everything in this hobby. I'm only having this die off in the frag tank. Parameter wise, I have been bouncing off the bottom for phosphates and low nitrates as well. However, in my old tank some of these same corals survived for a year in a zero'd out environment with dinos and pale as can be. When I moved them to the new tank with nutrients they turned around very quickly Most of these also survived my crazy alk swing I posted about last summer. I would think that if it were parameter related I would lose a couple at once. It's never more than one at a time. There are things I could do better. I'm still manually dosing, still have a GHL mini and a calcium reactor offline for no good reason. My parameter swings aren't very large, ALK is typically about 7.2, with no more than a 0.5 swing between doses for both tanks. I will check everything again. I feed fairly heavy because of the breeding clown pair. I'm taking next week off from work, so I'll be trying to get things more automated for both tanks. With Covid cases continuing to drop, I may be traveling again in the near future.

Lighting: My par is 100 on the bottom, 150-180 where my SPS are. My LED is a single Mitras tuned to the Coral AB spectrum by me. I measured ActiveAngel's Radions with a Spectral Radiometer. It's in an Aquatic Life Hybrid T5 setup. 2 blue plus, 1 coral plus, 1 actinic. I haven't touched the lighting or schedule since I setup this tank.

I dip Bayer, Revive, and then iodine before corals go into the QT. Still, I got some Interceptor to try it in case something got past them. I have to say that for one coral, a bottlebrush, it appeared to stop the STN and the polyp extension came back, but no obvious pests laying on the bottom afterwards. For two others it did nothing and they died within hours. I moved on to Furan-2 thinking bacterial also and I had some zoas that could use a treatment anyway. If was my first experience with dosing an antibiotic and I basically nuked my coral QT frag tank with the stuff. I followed the directions, but everything went super pale after 36 hours. It's supposed to be a 4 day treatment, I stopped after 3 and did a 80% water change, it's been a slow recovery.

I could have a flow issue. All these frags have grown 3-4 times what they were a few months ago. I've added one of the MP10's I have, but I've been lazy about adding the second one as I need to get around to repairing an extension cable and getting the MP10 moved into my accessories cabinet. I'm planning a layout change to split my frag racks in half and move my rock structure to get the SPS in the middle of the tank for peak lighting and ensure that there is an MP10 on either side set to reef mode to really move the water around.

I have ordered ATI ICP kits ,thanks @Adam for the suggestion, and I have been curious about the Aquabiomics bacterial analysis for about a year, so that is coming too. Of course BRS did a video on them the day I decided to order and backlogged the kits, so we will see when I can get the results.

 

[Cook]

Here's my mystery creatures under a stereoscope.

 

[NanCrab]

Wow these are creepy looking!

 

[ZapataInc]

@ActiveAngel know what this is?

 

[ActiveAngel]

The photos appear to be an amphipod, probably taking advantage of the weak and dying coral tissue.

As for the corals, my first recommendation would be to do a coral dip, as I think has already been done, and add a small supplement of iodide to the tank. Don’t overdose. In regards to coral dips, they can be very stressful on their own; Time is worse than intensity. So do the dip at full strength, but for no longer than the designated time. Then quickly rinse and put them back in the tank for at least 24-48 hours undisturbed.

But it sounds like you may be past that. If it is STN and has already been spreading from one colony to the next... then remove infected colonies from the tank. Identify infected tissue and cut frags that at least 1” away from anything infected. If you have any good healthy frags that were never within 1” of infected tissue, dip them, and return them to your display, and observe. For remaining frags, either toss them in the trash or put them in a separate QT tank. In my experience, everything within an inch or infected tissue will slowly die. If 1 piece of infected tissue is returned to the main tank, it has the potential to keep spreading. I don’t know if STN is bacterial, viral, fungus, or what.... but it is infectious. Manual control via removal seems to be most effective, my limited experience shows that it generally doesn’t jump colonies quickly.

 

[Cook]

New frag treatment: I clip each frag off the base and dip with Bayer, Two Fishies Revive, and end with an iodine bath and use a coral QT tank. I use pretty high concentrations: for Bayer it's 8 oz saltwater and add liquid until it's the color of milk, for Revive it's half a capful to 8 oz of saltwater, and the iodine bath is 10 drops Lugols to 4 oz of saltwater. Each frag is dipped for 5 minutes, blown with a turkey baster and well rinsed in between dips.

I think it could be bacterial at this point also thus the purpose of this thread, there is evidence that amphipods can eat corals though as well. As I look at the corals that were effected, this did radiate out from a specific frag. That person has sent shut down their tank. I'm interested to see if the Biological analysis can pick up anything using my display tank sample as a comparison.

Let me share an idea of the level of destruction because I understand why people quit this hobby now. These are my losses so far: SC Orange Passion (coral zero), Oregon tort, two Pocilliporas, Joe's Rainbow, Plum Crazy, Red Planet, Superman, Myagi Tort, Pink Floyd, and about four others that I can't remember right now. I started throwing the effected corals away as soon as they are attacked after my lack of success in trying an antibiotic.

 

[ActiveAngel]

Just keep in mind that if can you take an antibiotic approach, that won’t have any affect if it’s a virus or other microbe.

Actually, I find it very interesting that it is not only affected Acros but also Pocilopora. Those are pretty different from each other, and is evidence to suspect that it may environmental rather than microbial. But It’s hard to say.

 

[gainesvillereef]

Just keep in mind that if can you take an antibiotic approach, that won’t have any affect if it’s a virus or other microbe.

Actually, I find it very interesting that it is not only affected Acros but also Pocilopora. Those are pretty different from each other, and is evidence to suspect that it may environmental rather than microbial. But It’s hard to say.

I noticed the same thing. I have had 2 cases where a pocilopora appeared to have tissue necrosis. One was due to low nutrients in the tank and part major tank crash. And the other case was a very hungry shrimp. I caught the shrimp and the coral recovered very fast. @Cook do you have any montipora in the tank as well? If so, have you seen any necrosis with the montipora? I have found montipora to be a good canary coral for low nutrients.

 

[Cook]

I have not seen necrosis on the one montipora I have in there. Good information. I'll test all my parameters again and see what the results are. I'm not running my refugium, but I do skim. I do also have a shrimp in there that came with another tank recently but I believe he's a peppermint. If not it's a camel shrimp. Either way these issues started before he arrived.

 

[NanCrab]

I feel your pain. I’m having all kinds of unidentifiable issues with all of my SPS. Gonna send out an ICO test when I get out of the hospital.

 

[Cook]

@gainesvillereef I have several corals not doing well today including a montipora, so it's not just primarily my SPS.

This is what I have so far for today's parameters in no particular order:
Salinity 1.026 (Refractometer was just a tick off, I thought it was 1.025)
Phosphates: 0.052ppm (ULR Hanna phosphorus meter reads 17)
Nitrates: 2
Alkalinity: 6.9
Mag: 1320
Calcium: 365
Temp: 78.6F

Only thing I see off is the calcium and the nitrate is a little low. I made an add to bring back to 410. I'll be bringing the calcium reactor online this week.