Pink Birds Nest Coral

[RDuhb]

This is the third birds nest that has turned white starting at the base. No clue what's going on. They were fine for about 4 weeks then they started to fade. Does anyone have any thoughts on the cause? Is this STN/RTN? Other corals are fine. However, I'm not seeing a lot of growth.

Tank Parameters:
75g with 40g sump
Skimmer, GFO in reactor, Carbon in bags
Ca 420
Alk 9.0
Mg 1500
Nitrate 2.5
Phosphate <.25 (Using API kit. Measurement probably closer to 0)
1.025 sg
Temp 78

Lights:
DIY RapidLED kit with 24 royal blue (50% peak intensity), 12 neutral white (40%), 2 cool white, 6 violet UV (50%), 2 green (10%), and 2 red (10%). Light mounted 12" above tank with 80 degree optics. Max intensity from 11am to 5pm.

 

[Reefer54]

STN: Soft Tissue Necrosis
RTN: Rapid Tissue Necrosis

Often STN from the base up is a result of parameters being unstable.... Usually Alk swings. Do these corals bleach first, or bleach adn STN at the same time, and also, how fast does it occur......the picture looks like a starved coral with STN.

Those Phosphate readings are way high too...that would kill sps fairly quickly. .03 is kind of the common goal. you are talking almost 10 x that number.

 

[RDuhb]

Anyone else??

 

[barry_keith]

STN: slow lol not soft

usually related to alk or po4

 

[rromans88]

couple questions to help understand your situation:
What size tank do you have? gallons and dimensions
How long has your tank been set up?
What livestock is in your tank? fish and corals