sps bleaching

[PeTe PoLyP]

A few of my acropora are having some bleaching at the base. some are new additions, some aren't. The only recent change I made was cleaning the back of the tank and putting foil over the back. I have done this in the past with no negative effect. I have since removed the foil. Could what I'm seeing be caused by too much light? The parts that have bleached were parts that were normally shaded. It looks as if the polyps in the affected area are still there. I have 6 t5 over a 29g. Nitrate .5, phosphate .03, sg 1.026, ca 450, alkalinity 9dkh, mag 1300.

 

[PeTe PoLyP]

And for flow I have a jebao wp25, seio superflow 620, and a 175gph hob. All total near 1500gph in a 29g. I'm clueless as to what is causing it. I have taken pictures with my dslr and have inspected for redbugs, aefw, and eggs and have not seen any.

 

[PeTe PoLyP]

Could low phosphate levels be a cause of this? With the salifert test I come up with 0. The red sea is around 0.05. Several months ago I had a problem with the red sea kit having a false reading which led to over stripping phosphate. I lost many acropora as a result. Since this incident I have not removed any phosphate with media.

 

[PeTe PoLyP]

Any help?

 

[PeTe PoLyP]

This is the one I'm most concerned about. These pictures are 3 weeks apart

 

[PeTe PoLyP]

Any ideas or suggestions? I don't know what I'm missing here

 

[slapshot]

Could be PO levels but, low levels don't cause it to brown out. high levels do. This looks like a mariculture piece so having it turn brown is not unusual. They go through a lot getting here. Did you dip it?

 

[PeTe PoLyP]

Yes its maricultured. I used coral rx for a dip. The other corals I received at the same time are in good shape. As far as po4, I have no signs of any. There is a small spot of cheato that came on.a different coral base long ago. It remains the size of a done or smaller. There is no nuisance algae anywhere in the tank.

 

[slapshot]

The dip alone will cause it to brown out. When I used to use RX they always went brown for a few weeks. Just let it alone and it should recover. Look closely for AEFW for the die off. That is a symptom.i did not see any on the pictures so it might just have been stress.

 

[PeTe PoLyP]

Well I hope you're right. It didn't look bad until about 2 weeks after I received it. It actually started to gain some color in the first week, then this

 

[slapshot]

Well no way to tell for sure. Even in the best of conditions they can just go poof for no reason at all. Good luck, but I say the dip and it will come back. It can also become a totally different color. Again not uncommon with maricultured stuff. Our lights just don't equal the sun.

 

[Peter Eichler]

That is tissue necrosis, not bleaching. It can be caused by many different stressors, so it may be best to do a couple good size water changes. Also, more details on your system/equipment and what you use in it would help.

 

[PeTe PoLyP]

And for flow I have a jebao wp25, seio superflow 620, and a 175gph hob. All total near 1500gph in a 29g. I'm clueless as to what is causing it. I have taken pictures with my dslr and have inspected for redbugs, aefw, and eggs and have not seen any.

I have a six bulb 24" t5, 3x blue+, 1x coral+ 1x12000k, 1x actinic 03. I run carbon in the hob. I supplement with oceans blend 2 part and magnesium. 4 gallon water change every 2 weeks with reef crystals.

 

[rsaha]

That is tissue necrosis, not bleaching. It can be caused by many different stressors, so it may be best to do a couple good size water changes. Also, more details on your system/equipment and what you use in it would help.

Looks like it to me too. Start searching STN at the base. There are a number of causes for this so you'll have to figure out which one applies. Stripping nutrients too fast (phosphates in particular) is one cause, low flow is another (although that doesn't seem to be your problem) and there are more.

 

[PeTe PoLyP]

I had a slip up by removing phosphate too quick about 5 months ago. I haven't used anything to.remove phosphate since. I actually noticed the stn yesterday. It was on the back of the coral, and where its located is in a put of the base. Probably not enough.flow on that. What's happening on the other side is a different story. The polyps are still there and it isn't bright white like normal necrosis. In the past few days the whole coral started looking much worse, not just the base. It has lost its sheen and now looks like a matte finish. I think what's happening with the necrosis is something different from the rest. This coral has seemed hungry the entire time I have had it. It has its "feeders" out almost at all times. The other 2 corals I am having problems with aren't getting any worse. Somehow its all related. The purple one I have had for 11 months and it has only recently started to grow and color up, and now this. the bottlebrush was a new purchase, and it too is not any worse. About 1/2 of what had encrusted the plug is what is effected. The part that is shaded by the frag looks just fine. I did notice my bicolor blenny nipping near them today. Do you think that could be the problem?

 

[PeTe PoLyP]

The first 2 macro shots are the same area. The last one is of the opposite side. I very well may be wrong in saying the last pic is not necrosis. The only reason I think its not is.because it never exposed bright white skeleton. I have experienced rtn and stn in the past and to me it doesn't look the same. Where this is occurring is on a shaded part of the base. I exposed it to direct light, so could it be scorched? Both the tenius and bottlebrush were done this way. The purple one is new growth from the past 2 weeks and it has never moved. So that is troubling me.

 

[Jettareefer]

How is your overall on all of your corals ?

 

[PeTe PoLyP]

The other 7 acro look great. I have 3 new birdsnest frags that are coloring up nicely. My monti digitata growing like a weed. Pocillipora is.looking good too. Its just these 3, and 2 out of 3 are new. One from a very good online retailer, the other from lfs. The one from lfs is an ora frag.

 

[Jettareefer]

Your Parameters look to be in good shape I would stick with it, I would check for Pe at night as well as pest to double check.
-Addison

 

[PeTe PoLyP]

This was purchased at the same time.