zoa question

[cbrjenkins]

I have a frag of about twenty zoas not sure what theyre called but they are orange centered with bright green "tentacles" that Ive had in my tank for about a month now and wont open up. My other zoas, fire and ice and eagle eye, are thriving and growing...Ive tried putting the green zoas in different spots of flow and lighting all over the tank and they wont open. I have a 96w p.c system over a 20 gallon tank, any suggestion:confused2:

 

[cbrjenkins]

also

ammonia:0
nitrates:0
nitrites:0
p.h: 8.4
s.g: 1.022

 

[hn1]

Salinity seems a bit low. Where in the tank are they? What type of flow?

 

[cbrjenkins]

ive had them all over the tank, right now theyre at the very top of my highest piece of liverock, where the most flow/light is. I cant comprehand why the others are doing so good yet these wont do nothing, also i forgot to add that the piece of rock they are on has a slimy white substance on it, no idea what it is...should i frag the zoas and get rid the rock?

 

[cbrjenkins]

API master saltwater test kit

 

[ster]

Iodine seems to be the magical solution to most of my zoa problems.