Zoas Wont Open (Random)

[Dreichler]

So i have a JBJ 45 with 2 AI Primes and loaded with a variety of corals.  I have trachys, torches, hammers, lepton, zoas, palys, monti, scolys, etc.  Well the last week or so, strictly my zoas have not been opening up to their fullest, and they are starting to grow taller as if they are reaching for light.  Its definitely not the lighting because some of these zoas have been under it for almost 2 years now and all of them have grown under these lights.  The rocks that these colonies are one can't be taken out for dipping or anything like that.  My palys are not affected at all, they open fine, and nothing else seems to be effected at all.  Ive inspected the colonies of zoas several times per day and night and can't see a single nudi or any other sign of algal growth or parasite.  As of now, my dosing and feeding is:  Feed pellets once per day, occasionally a frozen mysis cube.  Dosing NO3:PO4-X daily after feedings.  Target feed corals reef roids 3 times per week.  Dosing Aquavitro Calcium and feel once per week.  I do 10g water changes once per week.  

My parameters are:

Salinity- 1.024 

Nitrate- ~5

Phosphate- 0.23

Alk- 7.7

Calcium- 415

Magnesium- 1450

 

Also, is it possible to revert the stretched out necks of the zoas or will they forever be that way now.