Zoas are not happy...

[ungp]

Recently added some zoas to my setup and hasn't been happy since. This was about 3 weeks ago. All others in tank are doing very well (fish, inverts and other softies)

Params are:
Ammonia = 0 or not detectable
Nitrite = 0 or not detectable
Nitrate = 0 or not detectable
SG = 1.022
KH = 142
Calcium = 380
pH = 8.0
Temp = 78-80 F

not running carbon

these params were taken 24 hr after the last water change, i've done 2 water changes in the last 7 day. About 15%-20% each change. I use RO/DI water. The TDS from my RO/DI indicate 0 ppm

What gives????

thanks in advance.