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Please help me prevent my tank crashing! Sudden swing in parameters, unknown source!

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Hello! As I am writing this I have just finished testing after experiencing what appeared to be a random bacterial bloom. I somewhat panicked, and did a 20-25% water change thinking the first thing one should always do is a water change if things are going sideways. After this, the cloudiness slowly faded away. A purple frilly gorgonian I had never bounced back though, and I removed him from the tank. After researching, I found that these gorgs can release a milky toxin and thought the 'bacterial bloom' was instead this toxin. I began running activated carbon in a small amount seeing as my other corals were all very visibly irritated. Fast forward a couple days, and its now been almost a week since my long polyp leather has extended polyps and I am suddenly getting readings of nitrite in my completely established tank? I havent had a nitrite reading since when I first cycled my tank with a LFS's established bioblock, over a month of nitrite reading zero, now it feels like my tank is cycling itself AGAIN and I dont understand why!

I am worried for my fish and corals and not sure the best next step seeing as I have been so hair-trigger to react so far and may have made it worse?

Please help, do I do another water change? Dose some sort of microbacter quick start (would take about 2 days to arrive)? What are the possible things that could have led to this so I can prevent this happening in the future?

Thank you so much anyone who is able to offer up help and advice, sincerely thank you!!!!

IMG_7603.webp
IMG_7617.webp
 
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Solution to pollution is dilution
Increase the size of the water change to make a significant improvement
New water should be “ideal”
You can’t change too much, or too often
 
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Hello! As I am writing this I have just finished testing after experiencing what appeared to be a random bacterial bloom. I somewhat panicked, and did a 20-25% water change thinking the first thing one should always do is a water change if things are going sideways.
Not sure if this is the first thing one should do but not the worst idea.
After this, the cloudiness slowly faded away. A purple frilly gorgonian I had never bounced back though, and I removed him from the tank. After researching, I found that these gorgs can release a milky toxin and thought the 'bacterial bloom' was instead this toxin. I began running activated carbon in a small amount seeing as my other corals were all very visibly irritated.
Using granular activated carbon was a good idea.
Fast forward a couple days, and its now been almost a week since my long polyp leather has extended polyps and I am suddenly getting readings of nitrite in my completely established tank? I havent had a nitrite reading since when I first cycled my tank with a LFS's established bioblock, over a month of nitrite reading zero, now it feels like my tank is cycling itself AGAIN and I dont understand why!
Nitrite is more or less irrelevant in saltwater, and I also get nitrite readings on ICP.

Not sure if it is possible for a tank to go through a cycle again unless you added medication etc, and your readings do not indicate to me anything to worry about.

I do question the accuracy of these API test kits.

I am worried for my fish and corals and not sure the best next step seeing as I have been so hair-trigger to react so far and may have made it worse?

Please help, do I do another water change? Dose some sort of microbacter quick start (would take about 2 days to arrive)? What are the possible things that could have led to this so I can prevent this happening in the future?

Thank you so much anyone who is able to offer up help and advice, sincerely thank you!!!!
Unless you see other issues, I do not believe anything went really wrong, and you seem to overreact, which is a normal behavior.

My recommendation would be to start a tank journal so that we have more background on your tank setup/equipment, fish, feeding, etc. This way we have a more holistic view of your situation and can provide more comprehensive advice if needed.
 
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Not sure if this is the first thing one should do but not the worst idea.

Using granular activated carbon was a good idea.

Nitrite is more or less irrelevant in saltwater, and I also get nitrite readings on ICP.

Not sure if it is possible for a tank to go through a cycle again unless you added medication etc, and your readings do not indicate to me anything to worry about.

I do question the accuracy of these API test kits.


Unless you see other issues, I do not believe anything went really wrong, and you seem to overreact, which is a normal behavior.

My recommendation would be to start a tank journal so that we have more background on your tank setup/equipment, fish, feeding, etc. This way we have a more holistic view of your situation and can provide more comprehensive advice if needed.
Thank you so much for your response to everything. As of reading this the long polyp toadstool has since done whatever this is? It appears to be splitting open? I am not sure if this is a sign of stress or reproduction, seeing as most of the corals in my tank are acting pretty pissed. Gorgs all keeping half their polyps in, clove polyps looking wilted, and now this... If the readings seem ok im not sure why everything is so pissed... Super concerning.

IMG_7619.webp


EDIT: just an hour ago it looked like the picture below, and i thought it was recovering. now it looks split like the above picture. just so confused...

image.webp
 
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Thank you so much for your response to everything. As of reading this the long polyp toadstool has since done whatever this is? It appears to be splitting open? I am not sure if this is a sign of stress or reproduction, seeing as most of the corals in my tank are acting pretty pissed. Gorgs all keeping half their polyps in, clove polyps looking wilted, and now this... If the readings seem ok im not sure why everything is so pissed... Super concerning.

View attachment 80547

EDIT: just an hour ago it looked like the picture below, and i thought it was recovering. now it looks split like the above picture. just so confused...

View attachment 80548
Do you have a full tank shot?
 
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This is the tank before, with the purple frilly gorgonian i thought was the culprit in the back.

tSP7mqd.webp


This is the tank as of right now with the frilly removed + aftermath since weird nitrite event currently happening
(sorry i am too scared to make the lights bright for a pic since everything is pissed right now and i dont have an orange filter)

asdfasdfasdfasdfasdfwerwerwerwer.webp

this is an innovative marine 20 gal long nuvo fusion. i removed the carbon this morning and the leather extended its polyps the furthest it has since the entire event went down and now... well he appears to be splitting? the salt i use is fritz pro RPM and i feed tdo small pellets / pe pellet mix with occasional frozen mysis. i add reef chili and AF phytomix for my NPS gorgs every now and then and have a super thriving copepod population in here.

really feels like everything was going right until suddenly it wasnt, and now the whole tank is mad
 
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With that many soft corals, carbon should be a common part of your husbandry but good instinct to add fresh carbon. Keep plenty on hand for days like this.

Hard to diagnose without more info.

A bacteria bloom could cause an ammonia spike and then nitrite, etc but I am also paranoid about soft coral warfare (since they dont have the same defenses as LPS)
 
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With that many soft corals, carbon should be a common part of your husbandry but good instinct to add fresh carbon. Keep plenty on hand for days like this.

Hard to diagnose without more info.

A bacteria bloom could cause an ammonia spike and then nitrite, etc but I am also paranoid about soft coral warfare (since they dont have the same defenses as LPS)
oh man this morning i removed the carbon because i read that it pissed off the long polyp leather and then the leather started finally letting out some polyps before ultimately splitting. as i write this he is all spiky again trying to let out polyps again even after the "split" or whatever that was. unsure if i add it back? so much conflicting info has made me unsure about running the carbon thats why i ultimately just took it out.

also, the system is around 2 months old

i swear this long polyp leather is hittin me with one of these right now

IMG_8903.webp
 
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also, those leathers and gorgonian types will slough off a top layer from time to time

carbon is good and beneficial if used properly
but large and frequent water changes will free you from the need for the carbon
 
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also, those leathers and gorgonian types will slough off a top layer from time to time

carbon is good and beneficial if used properly
but large and frequent water changes will free you from the need for the carbon
yeah its been about a week of them being pissed but no sloughing... seems like theyre pissed at something that is my fault here n i cant get to the bottom of what theyre pissed at though... but thank u for the info :) do u think i should put the carbon back? after removing it my leather appeared to try extending polyps again so i wasnt sure if the carbon was doing something detrimental
 
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If one or two corals look bad I wouldn’t do anything drastic. Just happens sometimes. You can do a large water change and put in some fresh carbon and wait.

Do you use RODI?
You should get a more reliable set of test—ie, no API. Salifert is well regarded. I prefer Hanna.
 
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If one or two corals look bad I wouldn’t do anything drastic. Just happens sometimes. You can do a large water change and put in some fresh carbon and wait.

Do you use RODI?
You should get a more reliable set of test—ie, no API. Salifert is well regarded. I prefer Hanna.
yeah ive got an RODI unit i use for all the tank water. ill look into replacing tests with salifert! but i tested my nitrite 3 times just incase and it was still the same every time :/
 
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Can you show a picture of the carbon brand you have been adding?

Did you ever test alkalinity?
just broke out my salifert alk test to check real quick, 10.9 dKH alkalinity was the reading. i use fritz pro RPM salt so it adds its own alkalinity and im using this carbon below

616FnbWDoVL._AC_SL1200_.webp
 
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There are a few situations where carbon isn't your friend but more often than not, it's a safe option to help remove unknown pollutants.

At 2 months, I would expect to see some events like this as the system matures. Bacterial blooms are pretty common in young systems and a chemical warfare release in that system won't take long to make things angry.

Seems like you're doing everything you can. Keep up with water changes.

Any inverts dying?
 
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There are a few situations where carbon isn't your friend but more often than not, it's a safe option to help remove unknown pollutants.

At 2 months, I would expect to see some events like this as the system matures. Bacterial blooms are pretty common in young systems and a chemical warfare release in that system won't take long to make things angry.

Seems like you're doing everything you can. Keep up with water changes.

Any inverts dying?
not that i know of unless a tiny marginella snail died under the sandbed and i havent seen. my skunk cleaner shrimp is doing well (despite trying to pounce on my royal gramma occasionally - unsure if this is to clean the gramma or an aggressive behavior) but my snails seem to be doing fine.
 
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