corals bleaching

[karina97]

for the last few day my corals have then bleaching out from the bottom to the top. I've done 10% water change. Cal is at 420, Mag 1320, Alk 130, Nitrate .01, Ammonia 0. I'm running 2 150 watt MH for 9 hours along with 2 96 watt PC for 12 hours. Can anyone help?

 

[willray]

Whats your ph and temp? Are they just bleaching or something else going on...STN,RTN,signs of predation etc.Anything new added lately...livestock or equipment?Got a pic?

 

[frank180reef]

sorry what is ur alk?

 

[karina97]

sorry what is ur alk?

alk is at 130, ph 8.4, temp 80.1

 

[stingythingy45]

130 ppm?

That 7.2dkh,a little low but not really bad.
Do you use any buffers or supplement anything?

 

[CrazyCorals]

more waterchange i would do 20% once a week.......

 

[MikeG]

What type of coarls are being affected?
What is the unit of measure on your ALK test kit ppm?
How is the stability of your temp and alkalinity?

 

[wrassefan]

as said usually alk/ph, salinity or temp swings

 

[karina97]

my temp fluctuates between 77 and 80 degrees each day. I have a ATO unit and my salinity is at 10.25 its been consistent. I'm running a calcium reactor

 

[karina97]

My alk is at 14.1dkh ph 8.29 and calcium 470. Sholud i lower my alk? My sps colors are fading

 

[willray]

Yes! Lower it slowly. Thats double what you had 10+- days ago,that is a real big swing for that time frame and 14 is high.Aim for 8-11 DKH max.Calcium is a bit high, target 420.