RTN and STN issues

[Llorgon]

I've been having issues with my tank since early summer. I had an SPS dominant tank with about 25 different frags. Most RTN, but a few that are still left are still slowly losing tissue from the base up. At first I thought the cause was nutrient related, but seeing as the same thing has started in my smaller tank with no nutrient fluctuations at least that I can tell from weekly testing I'm wondering if it could be the salt mix?

A bit more info, the tank is 75 gallons with sump, refugium with some poorly growing caulerpa and a protein skimmer. My issues started early July. I did my regular 10g water change, walked the dog and a couple frags had completely RTN'd when I got home. At that point, I added some fresh carbon in case something got into the water and tested my water. Water tests showed nitrates were at zero. I spent the rest of july dealing with RTNing SPS and trying to get nutrients in a good place. Nitrates went high then phosphates went to 0. I'm now at 3 weeks of stable nutrients and all major params.

Temp: 78
Salinity: 1.026
Alk: 8.9
Cal: 470
Mag: 1260
Nitrate: 11.7
Phosphate: 0.205

My problem is I am still seeing slow tissue death in the SPS from the base up. I also had something similar happen in my 25g. Did my regular water change and the SPS in the tank have slowly lost tissue. Not to the same extent as the big tank, but under the same circumstances. Except I have seen no large decrease in nutrients. Typically the tank tests at 2ppm nitrate and 0.04 phosphate.

Could the issue be the red sea salt? I am halfway through the bucket when things started to go wrong. I did have an ICP test done on the 75g. Maybe I am missing something else?

 

[Lavey29]

Phosphate still elevated and the swings to 0 cause issues. 0 nitrates was bad but you corrected it. How old is the tank? Do you dose alk and cal for stability?

 

[Llorgon]

tank is a bit over a year old. I do dose alk and cal and they have been stable throughout all of this. At least from what I can tell by weekly testing

 

[Ancient Mariner]

From the pics in your build thread, it looks like your LPS are doing well. What type of SPS have you tried? My guess is lighting. How about trying higher intensity?

i have a few acro frags that just haven’t done well for over a year and that’s under 400watt metal halides! I have been rearranging to get them to higher light and they seem to be improving.

i wouldn’t blame the salt.

 

[Llorgon]

From the pics in your build thread, it looks like your LPS are doing well. What type of SPS have you tried? My guess is lighting. How about trying higher intensity?

i have a few acro frags that just haven’t done well for over a year and that’s under 400watt metal halides! I have been rearranging to get them to higher light and they seem to be improving.

i wouldn’t blame the salt.

LPS have been doing fine at least until the last couple of days they have all been a bit unhappy.

I'm terrible with remembering the names of all the SPS, but I got the frags in Jan and they had all been growing. Would lighting cause sudden RTN and STN when they had been growing previously?

Honestly it's probably not the salt, but this has happened on 2 tanks after a water change. What else am I missing?

 

[Ancient Mariner]

LPS have been doing fine at least until the last couple of days they have all been a bit unhappy.

I'm terrible with remembering the names of all the SPS, but I got the frags in Jan and they had all been growing. Would lighting cause sudden RTN and STN when they had been growing previously?

Honestly it's probably not the salt, but this has happened on 2 tanks after a water change. What else am I missing?

Yes, low light will stress the frags over a long period of time and then you’ll get STN or RTN. It just happened to a milli frag and an ORA Plum Crazy in my tank. All other SPS have been growing very well.

 

[Ancient Mariner]

Also a still immature tank can have SPS growth initially then they shut down and fade.

I’d try again on down the road with higher light.

 

[Llorgon]

hmm. I thought low light would cause them to die quicker. I will have to check my par levels again. If I remember correctly, on the rocks the par levels ranged from mid 200 to high 400, but I will have to double check.

 

[Randy Holmes-Farley]

FWIW, I'm not really seeing a chemical reason for these issues.

 

[Llorgon]

FWIW, I'm not really seeing a chemical reason for these issues.

I was really hoping the ICP test would come back with something being wrong that would attribute to it.

Since this also started in my smaller tank at the other end of the house, I'm trying to come up with some sort of commonality between the two tanks. Which was why I was thinking the salt since both issues started up after a water change.

I've checked my RO/DI and all filters have been replaced at the beginning of summer and still read 0 TDS as of yesterday.

I have checked temp on both tanks with multiple thermometers plus the ones that control the temp(inkbird and apex), checked the salinity with calibrated hanna checker and refractometer. There must be something I have missed.

It could be the light in the bigger tank, but whatever caused this took out the best growing corals first.

I've added carbon in case there was something toxic in the water and it didn't seem to help with anything, I have been meticulous about not putting my hand in the tank if I have put on sunscreen that day.

 

[Llorgon]

When the lights came on this morning I saw another frag was completely white. It was looking fine yesterday....

 

[Llorgon]

Unfortunately, I can see more of the remaining SPS have lost more tissue since yesterday. The forest fire which had been recovering some and generally looking better is one of those hit now. With the exception of when this all started, most of the tissue loss seems to come overnight. I've looked over the tank multiple times with lights off and I don't see any sort of pests on the SPS.

Since I must be missing something, here is a list of everything on the tank I have looked into.

I must be missing something, here is what I have gone through:

ICP test - nothing jumps out as being the cause of SPS death. Some low trace elements, but from talking to water chemistry people on r2r nothing that should be causing these issues.

At home water testing - minus some nutrients bottoming out at the start of this, no major swings, everything controlled by dosing and has been stable. Nutrients are staying consistent going on 3 weeks now.

Stray voltage - Checked with my multimeter and my neighbours, no stray voltage.

Temp - controlled by Apex, checked by 2 floating thermometers and the temp gauge on hanna checker, it's right where the apex was programmed to keep it which is around 78.

Salinity - Checked by hanna checker and refractometer. Calibrated both and checked again. 1.025-1.026

Flow - no change to return pump settings or wavemakers, bumped the octopulse 2's up to 90% max from 85.

Lighting - Maybe this is the issue? 2 radion xr30 blue, 40% brightness, 100% intensity. I can't remember par readings, but I got these frags in Jan or earlier and I was seeing growth in them.

RO/DI - 0 TDS, checked as of last week. Filters replaced in june.

ATO - No issues with it, I did change my ATO reservoir from plastic home depot storage container to food safe dog food container. Washed with vinegar and hot water before use. That was in early June.

Water changes - 10-15g weekly using red sea salt. Issues started after a water change and also saw similar STN in my 25g after a water change. The red sea salt is halfway through the bucket. Recently tried tropic marin pro reef on Tuesday and saw a dead coral on Thursday.

Salt mix station - brute plastic garbage can, cleaned out every few months when stuff builds up. My mixing pump and heater are about 2 years old and seem fine. Hose to siphon water is probably 10 years old. Maybe that?

Dosing - red sea doser and red sea foundations powder for Alk, cal and Mag. I have found that I have been having to dose a lot of mag and having a hard time raising it. Currently dosing 5ml/day of mag. Where as when things were growing I was dosing 3ml cal. I only dose those 3 things.

Feeding - frozen mysis, calanus and one other I am blanking on the name. I also through in some pellets from time to time. Feed this tank the same as the 25g and hasn't changed for a couple years. I feed once or twice a day, add nori for the tangs.

Filtration - liverock in the tank, carbon in the sump, protein skimmer, poorly growing caulerpa in the refugium. Refugium is on reverse light schedule from the display lights. Filter floss is changed as needed.

Fish - all seem fine, 2 clowns, longnose hawkfish, yellow tang, blue eye kole tang. All happy and healthy. No new additions since May.

Invertebrates - various snails, no noticeable deaths, lots of eggs on the glass, all seem healthy and happy.

Pests - Nothing I can see on the corals, there are Aiptasia though.

Coral and placement - SPS are on the rocks, euphyllia on the sand in the corner of the tank, space invaders on the other side. Never seen any stinging from either going on at night. Both are far enough away from the SPS. Whatever is causing issues is hitting the SPS, the space invaders has lost tissue as well, but it doesn't seem to be getting worse. That was more back in July when all this started.

General equipment check - All seems to be in good working order. No rusting or exposed magnets that I can tell.

 

[Miami Reef]

Do you carbon dose by any chance (Red Sea NOPOX, vinegar/vodka/sugar)?

 

[Llorgon]

Do you carbon dose by any chance (Red Sea NOPOX, vinegar/vodka/sugar)?

I do not.

 

[Thales]

Can you tell us how they are losing tissue, or some pics?

 

[Llorgon]

Can you tell us how they are losing tissue, or some pics?

I can grab some pics this afternoon. They either lose it all at once, like it literally melts off in as quickly as an hour or on some of the slower ones it starts at the base and moves up. At least that's how most went at first.

The forest fire and the elkhorn, which were two of my best growing corals and the first I noticed having issues ended up losing patches of tissue.

With the few frags I have left, one was fine at lights out and completely white when lights came back on in the morning. Others, I have noticed it starting at the tips and working it's way down. One larger frag, which I can't remember the name is losing tissue on the base and tips and it seems to be slowly heading to meet in the middle.

 

[Miami Reef]

I do not.

Ok, at least that removes a variable.

 

[Llorgon]

Pics of what is being affected. Obviously I need to get the algae under control. Gha sprung up with the higher nutrients.

 

[Miami Reef]

Pics of what is being affected. Obviously I need to get the algae under control. Gha sprung up with the higher nutrients.

Wait,

Have you always had this algae when the acros had tissue necrosis?

I’d honestly be shocked if the acros didn’t die!

Solution: You need way more herbivores than you do now. And lots of manual removal. Get the algae under control and then try keeping the acros.

 

[Llorgon]

Wait,

Have you always had this algae when the acros had tissue necrosis?

I’d honestly be shocked if the acros didn’t die!

Solution: You need way more herbivores than you do now. And lots of manual removal. Get the algae under control and then try keeping the acros.

No, the algae came up after everything started to die off.