Losing SPS looking for ideas

[Poriferan]

Having issues with SPS. Here are the tank "stats"
Salinity: 1.025
Amm: 0
Nitrite 0
Nitrate: 20
Kh: 11
Ca: 450
Mag: 1300
Phos: .1 Hanna Meter

225 Gallon tank been running about a year.

I got as high as Kh 13 when the reactor was turned up too high. Maybe 6 weeks ago.

Weekly 15% water changes with Reef Crystals (note changed from IO about 4 weeks ago)

Run BRS Carbon in reactor. Have been changing weekly.

Last thing I scraped a bunch of palys off the rock in tank right before the mass exodus of most of the SPS. Even the Monti's bleached out and died at the bases but have regained about 70% of their color.

Not all SPS were affected. Some are still perfectly healthy (as far as I can tell) no color loss, maybe slower on growth.

This is my latest casualty. Two days worth of recession. Mili on right is frag of one on left (grown in different tank) that was placed there same day as recession started. Other frags of that mili on bottom of tank show no signs of stress.

Slow ramp up vinegar dosing started about a week after first round of loss.

Please give input. Ideas to fix, things to change or anything.

http://i626.photobucket.com/albums/tt346/crossbow422/IMAG0163.jpg (http://s626.photobucket.com/user/crossbow422/media/IMAG0163.jpg.html)

[LinkinReef]

Last thing I scraped a bunch of palys off the rock in tank right before the mass exodus of most of the SPS


These probably released their toxins and stressed the corals. Do you run any carbon?

[MARINECRITTERS]

Your alk is too high for carbon dosing, aim for 8.

[cheezybuda]

your alk is too high for carbon dosing, aim for 8.

+1

[Poriferan]

I have been running carbon and changing it weekly since the possible paly toxin poisoning.

I turned down the drip on the calcium reactor hopefully it will get the Alk down to around 8.

[wrott]

Yeah, try to stabilize params. Palys are not the issue, rapid changes to water parameters--like cleaning glass/sandbed will cause this. Many times its better to just let the tank grow--cyano/hair algae--don't clean for a couple of months and your SPS take off--keep alk/Ca steady, but dose slowly. A Ca reactor is best ime.
Looks like too much alk after looking at pics more closely--theres no quick fix to this, those corals are history unless you frag and move them.