Brown *stuff* suddenly appeared and kills! Please help identify it / microscopic pictures

[ragnarokas]

Dear users,

Suddenly out of nowhere my aquarium is covered with brown stuff. Snails died, and corals - especially polyps such as greenstar (which has been very thriving before), and zoa are retracted and seems to be very stressed as it is all covered by that brown stuff. It can be dusted off in some areas, so I thought about diatoms, but it may be sticky in others + snails die-off = maybe dino. Phosphates are not detected, nitrates around 3 . I have collected some of the stuff from the covered corals and put in under the microscope. I attached the images, but please check the video, as *it* moves and maybe this is more informative.

Do I understand correctly that it is some kind of diatom after all, not the dino?

Thank you very much,

Magnification 50x-100x



A.

 

[JustAnotherNanoTank]

In tank pics?

 

[45ZoaGarden]

Dear users,

Suddenly out of nowhere my aquarium is covered with brown stuff. Snails died, and corals - especially polyps such as greenstar (which has been very thriving before), and zoa are retracted and seems to be very stressed as it is all covered by that brown stuff. It can be dusted off in some areas, so I thought about diatoms, but it may be sticky in others + snails die-off = maybe dino. Phosphates are not detected, nitrates around 3 . I have collected some of the stuff from the covered corals and put in under the microscope. I attached the images, but please check the video, as *it* moves and maybe this is more informative.

Do I understand correctly that it is some kind of diatom after all, not the dino?

Thank you very much,

Magnification 50x-100x



A.

Yes, those are definitely diatoms. Are you using rodi water? What salt are you using?

 

[Garia666]

nm there not dino,s

 

[45ZoaGarden]

Dinos are small yellow/brown acorn shaped critters. Can you take a sample from the sand bed as well? How old is the tank?

Here’s a pic of dinos for reference...

 

[ragnarokas]

Tank is about one year old. One week ago it was thriving. Could diatom explosion be so harmful? And why the snails are dead?

I started to use Red Sea Coral Pro salt, but in no way I could believe it was because of if. Anyway if it is diatom, i will change new RO filter, and will change 50% of water plus will run rowaphos
Ech

 

[Fernthereefer]

What do you mean by suddently ? In 24 hours?

I have used a UV sterilizer and an in-sump sock to control them, althought it is not perfect.

The most important thing is what got out of balance? Did you add anything recently? How many water changes ?

Ideally you want to find the source, but I agree with the water change.

 

[ragnarokas]

I started to deteriorate 4 days ago , and 2 days ago green star did not extended their polyps. Water change 20% biweekly.

As I understand somehow a lot of silicates got in the water. It could be from salt(doubt), it could be from water - maybe my RO system went out of order, or maybe somehow my cheap phosphate remover I hold in the tank for the last several months let all the silicates back to water. Hard to guess

 

[Fernthereefer]

Good point on the RO going bad. What do you use in phosphate remover? Just curious

 

[ragnarokas]

I was convinced by some fellow that all gfo are the same, and that I should not waste money on expensive ROwaphos, and he sold me some noname stuff.

Maybe it was not the best idea to buy it.

 

[Fernthereefer]

Hopefully somebody with more experience will chime in, but in my opinion that's not the source of your problem. If you have not changed/added anything other then water changes, then the RO water is the likely culprit.

You should use a TDS meter often to make sure the RO is good before using.

 

[ragnarokas]

Hopefully somebody with more experience will chime in, but in my opinion that's not the source of your problem. If you have not changed/added anything other then water changes, then the RO water is the likely culprit.

You should use a TDS meter often to make sure the RO is good before using.

I constantly measure it and it shows below 10 ppm. So technically it should not be a problem. I don't know...maybe overfeeding ? I put one cube of frozen brine shrimp every other day in the 100 liter aquarium with 4 fishes. But it was thriving for half a year, so again...do not know. Will invest 100 eur to buy new RO filter and Rowaphos and will see how it goes.