Acro turning white

[sluicebox]

I've had this acro for about 8 weeks in the same place. It is one of the first SPS corals I placed in my new tank. It is now turning white from the base upward. Is it getting too much light? I am new to keeping SPS and need help. Should I just move them down in the tank. I have the Red Sea Max S650 (150 gallons) with 800 watts of T5. This coral is placed in the top third of the tank. I keep the lights on for 8 hours with the intense lighting for only 6 hours.

The water parameters are good: ph = 8.15; sp. g. = 1.025; ca = 397; alk = 9.9; mg = 1350; NO3 = 0; PO4 = 4 ppb

Also, I have a pink stylophora that seems to be losing color. It is about half way down in the tank. Any advice?

 

[greg0385]

Looks like STN. My opinion is either try and frag the healthy part. Or some people have used superglue to glue over the dead area into the healthy area. If you do nothing it will continue to spread.
Many reason stn happens, stability may be the problem or maybe something else.
Goodluck
also you might try dipping to make sure it isnt a pest

 

[Dowtish]

Agreed. It needs to be fragged and just hope for the best. The oink stylo requires really intense light. I have one that was pink and then turned a dark purple, and never went back. I would move it up.

How do you dose for alk and cal? 2 part or a cal reactor?

 

[sluicebox]

Right now I am dosing 2 part. I have a kalk reactor but took it off line as the Ca levels were too high. I plan to start the kalk reactor again when the tank begins using more Ca.

 

[Dowtish]

Well you listed your calcium at 397, which isnt too high. anything above 450 is high. If you get a spike in calcium, your alkalinity will immediately drop as well, and this could be your cause for the STN on the coral.

 

[sluicebox]

The Ca is stable now and has been since I began using 2 part. Before I started with 2 part dosing, I just replaced top off water through the kalk reactor, my Ca levels were always over 500 ppm. Also, this is a relatively new tank with mostly frags so the Ca demand is not very high. But, your point is well taken as it has taken some time to get things as stable as I would like to see them. Hopefully, that will settle down now.

 

[Dowtish]

I hear you on the demand not being large at this point. Just try to get your cal and alk dialed in at the preferred levels, and give the tank a few more months, and I'm sure you will be able to have some happy SPS.