Confused. Tips are burned

[VanDalsenReef]

Hey everyone,
So I have gotten a few acropora frags and they had been doing great for about a week. Then they started to in a way brown out and get their tips burned. So I tested my alkalinity over 24 hours and it barely changed from 7.8 to 8. I also tested my no3 and po4. They were 10 and 124ppb so I dosed Lanthinum chloride to bring it down to 34ppb. Could I have dropped my po4 too fast and the corals then stripped some tissue. They also look "skinny" less plump than when I got them. Polyp extension is also a minimum.
I am running 2 compact orpheks and 4 or120 blues/uv on a standard 90 gallon I turned the orpheks from about 40 percent max to about 90 percent. Could that also be the issue?
Alk 7.8-8.2
Cal. 450
Mag. 1350-1400
Po4 .1
No3 5-10

90 gallon 48×18x20.
2 compact orpheks
4 or120
Skimmer
Brs 2 part with tropic marin trace
refugium (opposite schedule)


I don't know what could have happened.

 

[VanDalsenReef]

Sorry about the crudy pictures.

 

[mikereefing]

I have issues with burnt tips whenever my phosphates tank too fast or drop below 0.04.

 

[VanDalsenReef]

I have issues with burnt tips whenever my phosphates tank too fast or drop below 0.04.

Should I just try to watch and keep as stable as possible? How long does it take for them to recover and should I trim the tips off to get growth started back?

 

[mikereefing]

Definitely try to keep everything stable. For me, I've had mixed success with cutting the dead tips. I currently have a PC rainbow colony that grew back over the cut tips after two weeks. I've also had a diff colony completely RTN after I did that as well. I would try to just leave everything alone and keep things stable..and if the tips don't heal on their own then maybe consider cutting if the necrosis isn't stopping

 

[VanDalsenReef]

Definitely try to keep everything stable. For me, I've had mixed success with cutting the dead tips. I currently have a PC rainbow colony that grew back over the cut tips after two weeks. I've also had a diff colony completely RTN after I did that as well. I would try to just leave everything alone and keep things stable..and if the tips don't heal on their own then maybe consider cutting if the necrosis isn't stopping

Should I drop the percentage of my lights down?

 

[Rmckoy]

Exactly the same as I experienced not too long ago .

phosphates were extremely high so I added rowaphos in a reactor to lower them .
shortly after 90% of my sps turned brown .
24 hours later they almost melted and were dead .

 

[Rmckoy]

Weird part is . All of a sudden I have a recent explosion of coralline

 

[VanDalsenReef]

Exactly the same as I experienced not too long ago .

phosphates were extremely high so I added rowaphos in a reactor to lower them .
shortly after 90% of my sps turned brown .
24 hours later they almost melted and were dead .

I'm so sorry. Mine aren't bottomed out and this has been a week so it's been a relatively slow decline in health

 

[mikereefing]

Should I drop the percentage of my lights down?

I don't have those light so I can't comment how much increase in PAR that means. However, that increase from 40% to 90% sounds pretty profound and might have contributed to extra stress to the corals. This may have also contributed to the burnt tips together with the nutrient shock. Personally I would bring it back down to when they were happy and tackle one issue at a time. Once they've regrown from more stable parameters, slowwwwwly increase the light percentage if that's what you want to do

 

[amazongb]

You did a lot in a short period of time.. raise light intensity and reduced P04. Go slow... I've been tinkering with adding 5% whites to my lights over weeks so I don't shock anything..