Need Help – Corals Suddenly Dying

[lordZ]

Hi everyone,


I’m hoping someone can help me figure out what’s going on with my tank.


Over the last few days, the water has started looking cloudy, and most of my corals—especially my LPS—have become very retracted and are now starting to lose tissue.


I’ve tried a few things already:

• Dosed Baktoshot.
• Increased feeding in case the corals were starving due to undetectable nutrients.

The only recent change I’ve made was increasing my alkalinity with XEPTA KH, going from 6.9 dKH to 7.7 dKH.


Here are my current parameters:

• Temperature: 25.4°C (77.7°F)
• Salinity: 1.025
• pH: 8.2
• Nitrite (NO₂): 0 ppm
• Nitrate (NO₃): 0 ppm
• Phosphate (PO₄): 0 ppm
• Calcium: 410 ppm
• Alkalinity: 7.7 dKH
• Magnesium: 1430 ppm

These values have been very stable since the tank was set up.


At this point I’m running out of ideas. Does anything stand out to you? Could raising the alkalinity have triggered this, or is there something else I should be looking for?


Any advice would be greatly appreciated. Thanks in advance!

 

[Mr. Mojo Rising]

Can you post the pics in white lights only please, its hard to see when its blue. Can you post a full tank picture so we can see the whole thing? What kind of lighting do you have? What do you have for water movement? How long have you had the corals before they start declining? Thanks

 

[lordZ]

Can you post the pics in white lights only please, its hard to see when its blue. Can you post a full tank picture so we can see the whole thing? What kind of lighting do you have? What do you have for water movement? How long have you had the corals before they start declining? Thanks

Yes.

I have 7 orphek OR4 3 white 3 blues 1 UV.

3 MP40w + VECTRA M2

780l + 220l sump

4 month. Last week I put one rhodactis and one favites.

 

[Subsea]

White light please means, only white light.

PS: I agree with Miami Reefer, your bottomed out nutrients are not a good thing. When phosphates bottom out, opportunistic Dinoflagellets thrive and when coupled with zero inorganic nitrate Red Tides thrive.

 

[miami_reefer]

I think your bottomed-out nitrates and phosphates are the main culprit here.

Raising your alk with zero nutrients is a classic trigger for coral tissue loss because their metabolism speeds up, but they have no food to support it. On top of that, the Baktoshot and heavy feeding caused a bacterial bloom (hence the cloudy water) which strips oxygen from an already stressed tank.

I'd pause the Baktoshot, crank your surface agitation to get oxygen levels back up, and consider directly dosing liquid nitrate and phosphate to get your levels off absolute zero. Hang in there!

 

[lordZ]

Thanks a lot!

I send you pictures with white All light I could. Orphek doesn’t allow me to leave blue light at 0.0


I’m going to start following your advice. I’ve ordered two bottles of liquid nitrates and phosphates. In what order would you start using them?

 

[Mr. Mojo Rising]

When I zoom into your corals, a lot of them have their mouths open, IMO it supports the comments that the corals are hungry.

 

[EnterName]

I’m going to start following your advice. I’ve ordered two bottles of liquid nitrates and phosphates. In what order would you start using them?

Dosing nitrate won't help much. Nitrate needs to be converted back to nitrite and then ammonia which requires certain trace elements and energy, which your corals might be lacking already.

It would be much more effective if you dosed ammonia: https://www.reef2reef.com/threads/diy-ammonia-dosing-for-low-nitrate-systems.987087/

You might also be able to dose phosphate more cost effectively using this recipe: https://www.reef2reef.com/threads/diy-phosphate-dosing-recipe.1109919/

 

[Subsea]

Thanks a lot!

I send you pictures with white All light I could. Orphek doesn’t allow me to leave blue light at 0.0


I’m going to start following your advice. I’ve ordered two bottles of liquid nitrates and phosphates. In what order would you start using them?

Dose at the same time. Follow vendors recommendations.

Know this, when I sent Gracilaria Parvispora to regional agriculture lab, the ratio of N, P, K was 30/1/150.

 

[lordZ]

Okay, I'll start by dosing phosphate, which I should have available tomorrow or the day after. In the meantime, should I continue feeding the fish and corals? Would it be a good idea to do a water change?

Thanks in advance for your help!

 

[Subsea]

Okay, I'll start by dosing phosphate, which I should have available tomorrow or the day after. In the meantime, should I continue feeding the fish and corals? Would it be a good idea to do a water change?

Thanks in advance for your help!

Yes, feed fish.

What is your normal maintenance schedule for water changes?

 

[lordZ]

Yes, feed fish.

What is your normal maintenance schedule for water changes?

Once a week. And feed the corals with fito once a day.

 

[Subsea]

Once a week. And feed the corals with fito once a day.

How big is your tank and what volume gets changed. Details help.

 

[lordZ]

How big is your tank and what volume gets changed. Details help.

1000l the entire system. 780 principal tank. I chang over 10% in a week.

 

[Privateye]

Do you use a protein skimmer and/or UV sterilizer? Those pieces of equipment can help prevent bacterial blooms. I'd stop dosing the bacteria supplement until you get the clarity under control.

I agree that your nutrient levels should be addressed, but I don't feel like we're seeing the typical signs of low nutrients right now. Perhaps with the coral recession, but we're not seeing dinoflagellates and it doesn't explain the water clarity issues. If these things all started happening at the same time (it sounds like your NO3 and PO4 haven't changed recently) then I'd lean towards addressing what changed first. If the corals still look unhappy after that, then definitely go after the nutrients next. It's hard to know at this point whether we're looking at one larger issue or two smaller ones together.

 

[lordZ]

Do you use a protein skimmer and/or UV sterilizer? Those pieces of equipment can help prevent bacterial blooms. I'd stop dosing the bacteria supplement until you get the clarity under control.

I agree that your nutrient levels should be addressed, but I don't feel like we're seeing the typical signs of low nutrients right now. Perhaps with the coral recession, but we're not seeing dinoflagellates and it doesn't explain the water clarity issues. If these things all started happening at the same time (it sounds like your NO3 and PO4 haven't changed recently) then I'd lean towards addressing what changed first. If the corals still look unhappy after that, then definitely go after the nutrients next. It's hard to know at this point whether we're looking at one larger issue or two smaller ones together.

Yes, I do use a protein skimmer, but I don’t have a UV sterilizer.


As of today, after following the advice from everyone in the thread, the situation hasn’t improved—in fact, it’s getting worse. Almost all of my corals have died, the water is still cloudy, and my water parameters haven’t changed at all.


I’ve stopped dosing alkalinity (KH) in case that was contributing to the problem, and I’ve also stopped dosing the bacterial supplement as suggested. Unfortunately, I haven’t seen any improvement yet. At this point, I’m not sure what else I can change or test to identify the root cause.

 

[EnterName]

Do you use a protein skimmer and/or UV sterilizer? Those pieces of equipment can help prevent bacterial blooms. I'd stop dosing the bacteria supplement until you get the clarity under control.

I agree that your nutrient levels should be addressed, but I don't feel like we're seeing the typical signs of low nutrients right now. Perhaps with the coral recession, but we're not seeing dinoflagellates and it doesn't explain the water clarity issues. If these things all started happening at the same time (it sounds like your NO3 and PO4 haven't changed recently) then I'd lean towards addressing what changed first. If the corals still look unhappy after that, then definitely go after the nutrients next. It's hard to know at this point whether we're looking at one larger issue or two smaller ones together.

I assume an algae/bacteria bloom just keeps nutrient levels down and turns the water cloudy.

Dinoflagellates are not a necessity when nutrients are bottoming out, it's possible the ongoing bloom is not allowing much dino growth right now.
The experiences people make with bottoming out nutrients seem to differ and I could imagine the algae/bacteria bloom is producing toxins or irritates corals in a different way.

UV sterilization or sitting it out seems to be the only solution. Without UV I actually struggle to decide if dosing nutrients is a good idea or not.

 

[Privateye]

Yes, I do use a protein skimmer, but I don’t have a UV sterilizer.


As of today, after following the advice from everyone in the thread, the situation hasn’t improved—in fact, it’s getting worse. Almost all of my corals have died, the water is still cloudy, and my water parameters haven’t changed at all.


I’ve stopped dosing alkalinity (KH) in case that was contributing to the problem, and I’ve also stopped dosing the bacterial supplement as suggested. Unfortunately, I haven’t seen any improvement yet. At this point, I’m not sure what else I can change or test to identify the root cause.

I'm really sorry to hear that. If they declined that quickly, then I suspect nutrient issues even less. Again, still good to keep them in the right range, but it seems there's something else at play.

Perhaps I missed it, but have you tried any water changes? If not then I highly recommend doing that next. I'd also add some Purigen in a bag to an area of the sump with decent flow. Perhaps a Poly Filter too in case the color change indicates a contaminant.

I once had a 10 gallon that couldn't keep any inverts alive. I added a bag of Purigen and it solved the problem.

I once saw corals die this quickly at a store I worked at. They had purchased a new pump for the system recently. After adding a Poly Filter to the sump, it turned blue, indicating copper. They ripped the pump apart and found a brass mechanical seal.

Carbon could work too, I've just had better luck with Purigen.

 

[BryanM]

I suspect, due to cloudy water, a bacteria issue. Running carbon can help, as well as large water changes. A UV would likely help too.

Long term addressing no nutrients is needed.

 

[lordZ]

As of today, after several water changes, adding activated carbon, and placing a good amount of filter floss throughout the sump, I'm finally starting to see some light at the end of the tunnel.

All of the algae in the tank died, along with a large portion of my corals. I've never seen anything happen so quickly.

The only survivors were one Euphyllia, one Rhodactis, one Ricordea, and a few Zoanthids. Today, some of them have even started to open up again.

To be honest, I still don't know what caused all of this, but there's a long road to recovery ahead.

Thank you very much to everyone who took the time to help and offer advice.