Totally Stumped!

[Gondore]

I was hoping someone here may be able to provide me with some guidance on what may be off with my tank.

I am running a 140 Reef Savvy rimless tank with a following equipment:

- ATI Sunpower 8 bulb with xho Reefbrite
- Avast kalk reactor
- Octopus 3000xp skimmer
- brs GFO and Carbon reactor
- 2 mp40s for flow
- puckani rock from BRS
- live sand (fine grain)

I am doing weekly water changes of about 15 to 20 gallons and change the gfo and carbon around the month mark. The tank has been running for around 6 months. I have about six years experience keeping an sps tank. My last tank was a 90 gallon that was around five years old and sps were literally feeling up the entire tank.

My issues is this brown fluffy stuff that grows on my rocks no matter what I do. I can't identify what it is though I have looked high and low. The weird thing is that this stuff seems to kill pretty much every fish I but in my tank. The weird part of all this is that my sps colors are average to above average and lps seem to be fine too. Growth isn't were I think it should be but otherwise the corals are fine...it's just the fish.

I am stumped at this point as to what to do. All parameters in the tank are good so it's something I can't test for. Does anyone have any suggestions at all?

[dadummy]

see if the brown stuff is dinoflagellates

[spkennyva]

Seems like if its killing fish then it might be some type of bacteria. I started my reef with dry rock, which grew some white/brown fluffy stuff. I thought it was due to lack of flow, so I put a powerhead down to improve the flow. About an hour later every fish in the tank was dead. Sounds like you may be dealing with the same stuff.

[Gondore]

Seems like if its killing fish then it might be some type of bacteria. I started my reef with dry rock, which grew some white/brown fluffy stuff. I thought it was due to lack of flow, so I put a powerhead down to improve the flow. About an hour later every fish in the tank was dead. Sounds like you may be dealing with the same stuff.

This sounds very similar. It is brown/white and can be blown off with a baster. When I do blow it off I notice the fish gills going crazy sometimes. What did you do about it?

[gweezpie]

I have battled the same stuff for awhile now. I have kept reef tanks for 15 years, and just started back 2 years ago, but I have never battled this before. At first I thought Dino's, but its funny snails and crabs seem to eat it. My fish don't die, but my corals are suffering color and growth issues... I'd like to blame this stuff, but not sure that is accurate. I finally used DinoX on it...helps but did not totally eliminate it. I have no signs of hair algae, cyno or slime ....no algae of any kind except this stuff. No diatoms either.
So, my advice...fauna Marin DinoX. Dose per instructions....you will notice a real improvement. Hopefully, it will eliminate it for you.

[Stenopus]

change salt that you are using, than sand, than rocks. This is the way you have to follow.

[SpSChief85]

I would say try some of Boyds red slime remover... it kills bacteria... since you have no fish I think it's not a bad approach before replacing sand and rocks. Also I would try any other bacterial treatments available and see if you achieve any results. I saw this before on a guys tank and it went on for over a year... was a mess... not sure if he even rectified the problem. I hope my advice helps or may lead to a more educated approach from a fellow reefer.

[NaturalReef]

My opinion is don't kill the bacteria and add a variety of it. Prodibio digest and bioptim does a great job at taking away brown algae. My pukani leached for a good 6 months and I lost a lot of beautiful corals from being smothered by the stuff!
Parameters were spot on as well, but I use led lighting which grows brown algae like crazy and my pukani was the source of phosphates. I was skeptical of Prodibio, but after using it now for a month(dose every two weeks) I see the brown algae is withering away. Hope that helps....

[spkennyva]

What did you do about it?

There was one main rock that had the most of this stuff. I pulled that rock and placed it in a qt for about 9 months. The same rock is now back in my main tank without issue. While in the qt, I would do periodic water changes and never saw the same stuff during the qt period. I suspect that this is a dry rock issue, and probably only certain types of dry rock get it, but this is total conjecture on my part.

[jroovers]

That fluffy brown algae is normal when starting up a new system, as are dinos, cyano, hair algae, etc., especially if you are using new, uncured rock. My tank is about 7-8 months new and the brown stuff is subsiding. If your corals look good, that is the main thing. Keep up with your routine, ride it out, and resist the temptation to do anything drastic or waste your money on snake oil, your tank. Baste your rocks before water changes, vacuum your sand bed if you have one, and focus on good flow and strong skimming and finding your nutrient balance, and eventually you'll be in business. Patience is key.

Edit: The brown fluffy stuff should not kill your fish. I've had plenty of it since start up and not had any fish issues, so my guess is its something else, potentially sickness/water chemistry issue. How do you know the brown stuff is causing the fish deaths?