Wuestion about STN from the base with a powdery substance

[Aqualund]

Okay, so this is occurring at my coral farm, and its pretty frustrating.

parameters are:

SG: 1.025
Ca: 440
Mg:1500-1600 (high...but adjusted and returning back to 1300 ranges)
NO3: 2ppm
PO4: .36

Lighting is 6500k 250w metal halide with supplemental Lumia leds. Lumias are ramp/down on for 10 hours and the halides are on for 6 hours.

Flow is decent but not ideal/perfect over every inch of the propagation tank.

Problem: I'm getting this "dust" build up at the bottom of the sps...not all of them...I'd say 80% of my SPS are doing amazing...but there's always that one or two that develop this dust...it slowly takes them over the course of 3 weeks and eventually die. Then...another one shows signs and develops the same problem.

This seems to be exclusive to the smaller frags/colonies and doesn't really affect the large mother colonies.

I have dipped weekly with bayer and made a concerted effort to remove the dusty crap. There are no bugs or flatworms. Also, looking under a microscope, the dust just appears to be dust bound together by whatever.

Has anyone encountered this, and have any suggestions?

 

[trueblackpercula]

I cant be certain but the second to last picture looks like AEFW

 

[Aqualund]

It's quite possible but I couldn't find anything. Looking at these pictures again it seems possible on a couple of the pieces....but then that doesnt really explain the dusty stuff tho.

 

[ThorEffex]

How's the flow in your system?

 

[Aqualund]

I have a lot of laminar flow, but relying on the collisions of the many sources to provide the randomness. So It's definitely probably better than most...but I discount it because its not some really intense random tidal pulsing that I feel would be ideal. That's the only time I would think my flow is actually sufficient.

As it stands right now, and after doing a lot of reading...I'm inclined to think this is aefw...I now need to do better investigation of the corals.

 

[bogg]

Photo 5 def bite marks
Possible pathogen also bouncing around

 

[Aqualund]

Photo 5 def bite marks
Possible pathogen also bouncing around

Could you give me some guidance on the different types of pathogens to look for...just a website that has good information on them?

 

[bogg]

Ime there's nothing you can do

 

[dartier]

Have you looked at these out of the tank with a magnifying glass? Those cheap handheld USB microscopes are great for this. Oops I just saw that you checked with a microscope.

The first and second last photo look like there may be nudis on the coral. Obviously not the montipora eating nudis, but perhaps the more general coral eating variety. Any chance the 'dust' is what was left of disintergating nudis after being dipped? Any sign of egg clusters?

Dennis

 

[Reef Bass]

+1 for bite marks, likely aefw, in pic 5.

You may have more than one issue going on. Looks like possibly a couple red bugs in the upper right corner of pic 1.

I've seen "dust" like that on montis when monti eating nudis have been chewing on them. But those are acros.

 

[PaleHorse]

Whats your alk? why was mag high were you having problems?

looks like the other ones are headed for death also.

 

[Aqualund]

definitely AEFW. thanks for the help guys/gals.