el_pinguino
New member
I have a mature (10 year old) 10 gallon tank that is looking quite unhealthy at the moment. And I am at my wits end as to what might be the cause. The tank had been very stable up until the last 3 weeks or so.
Temp: 79F
Salinity: 35ppt
Alkalinity: 6.9dkH
Calcium: 450ppm
Nitrates: ? (I haven't had to test this in years and no longer have a tester)
Filtration: HOB Protein Skimmer, GFO, occasional carbon
Additives: ESV B-ionic 2-Part
I first noticed something wrong when my Xenia began to shrink. I had a lot of Xenia (about 1/4 of the tank real estate). They are now almost completely melted away. And a large cyanobacteria and diatom outbreak has taken their place. I haven't seen cyanobacteria since I first cycled the tank 10 years ago.
Here is how it seems to be affecting the other inhabitants.
Green star polyps: closed or only partially extended throughout the day (previously very healthy)
Zoanthids: closed or only partially extended throughout the day (previously very healthy)
Clove (snowflake) polyps: almost completely shrank away (but i'm kind of glad they're gone)
Frogspawn: seemingly unaffected
Ricordea Florida: seemingly unaffected
Seriatopora (Birdsnest): seemingly unaffected
Fish: (1 occelaris clown, 1 azure damzel) seemingly unaffected
Inverts: seemingly unaffected
I did a 25% water change last week. Yesterday, I did 50% water change, siphoned out most of the cyanobacteria, and added some activated carbon. All the cyano came back within 24 hours.
My theory is something killed the nitrifying bacteria.
Temp: 79F
Salinity: 35ppt
Alkalinity: 6.9dkH
Calcium: 450ppm
Nitrates: ? (I haven't had to test this in years and no longer have a tester)
Filtration: HOB Protein Skimmer, GFO, occasional carbon
Additives: ESV B-ionic 2-Part
I first noticed something wrong when my Xenia began to shrink. I had a lot of Xenia (about 1/4 of the tank real estate). They are now almost completely melted away. And a large cyanobacteria and diatom outbreak has taken their place. I haven't seen cyanobacteria since I first cycled the tank 10 years ago.
Here is how it seems to be affecting the other inhabitants.
Green star polyps: closed or only partially extended throughout the day (previously very healthy)
Zoanthids: closed or only partially extended throughout the day (previously very healthy)
Clove (snowflake) polyps: almost completely shrank away (but i'm kind of glad they're gone)
Frogspawn: seemingly unaffected
Ricordea Florida: seemingly unaffected
Seriatopora (Birdsnest): seemingly unaffected
Fish: (1 occelaris clown, 1 azure damzel) seemingly unaffected
Inverts: seemingly unaffected
I did a 25% water change last week. Yesterday, I did 50% water change, siphoned out most of the cyanobacteria, and added some activated carbon. All the cyano came back within 24 hours.
My theory is something killed the nitrifying bacteria.