Monti Plates Bleaching...5 kinds!

So I have noticed that some rather mature plate corals I have are bleaching out..Orange plate 8" diameter, green w. blue polpys apx 8", idaho grape, green anacropora, and a 3" ornge encrusting and orange setosa are all bleaching.

Other corals like birds nest, stags, brains, lobos, duncans, cyphastrea and chalices okay....

Parameters:

CA 400 +a dose after test
Kh: 8 +a dose that is mixing right now
Mg 1200 + a large dose as of last night
Phosphates 0-.25
Nitrates:20 triple check...Water change and some fresh Seachem Denitrate?

I did see some warm temps in the tank last week...84.5 tops...for maybe 3-4hours in the 83-84.5 range.

 

IMHO - I think that those temp spikes may well be the reason for the colour loss on the montis

your current parameters on Calcium and Alk are fine IMO
The Mag is as you noticed a bit low but I dont think thats the reason for the color loss

are you sure its bleaching, as another common problem with plating corals as they get larger and more intricate is the edges going soft and mushy, and thats often caused by lack of flow

Steve

 

well I hate to state the obvious but since all 5 types are montipora and none of your other sps are bleaching... do you think it could be montipora eating nudis?

have you lost any fish (preferably a wrasse) recently or have you added any frags recently? My dad got some MEN that rode in on zoas somehow

or temp could possibly explain it... except it is really weird that no other sps bleached from the temps

 

Hmmm I did not think MEN munched on setosa or encrusting types???

 

I have heard of a friend loosing their Jedi Mind Trick in only a few days due to MEN, so i know they can go after encrusting... but I dont know if they go after setosa types though?

IME with them, some nudis are very selective upon what types they will eat, even between different colors of the same species. But if I remember correctly, the ones that reefmonkey had were eating any and every type of monti that he had.

 

Oh, yeah, they can destroy whole colonies. They are really tiny and hard to see. I have pictures of them somewhere. brb.

 

They hide up under the rim, and blend in very well. The nudi came out in the second shot only because it was in a Lugol's dip.

 

Dang just great! I thought they only ate the plating montipora. A new pest to worry about, here I thought I was pretty safe getting encrusting or setosa. Nope guess not.

 

You're never safe to go in the water! lol!

 

yeah, you shoulda learned your lesson from red bugs!!! QT everything